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Structure
1.0Introduction
1.1 Classificationoftextile fibres
1.2 Generalproperties oftextile fibres
1.3 Difference betweencellulose and synthetic fibres
Learning Objectives
After studyingthe chapter you willbe able to understand various terms
associated with fibers.
• Classifythetextile fibers.
• List out various generalproperties oftextile fibres.
• Distinguishbetween thevegetable and synthetic fiber.
Unit Preview
This unit gives the information regarding definition ofterms, staple and
filament i.e. classificationoftextile fibresand generalproperties oftextile fibres.
1.0 Introduction
Theword textileisderivedfromtheLatinterm“texture” forwovenfabrics.
Thus by textiles we understand those objects which have been prepared by
weaving. Textile have an important bearing on our daily lives and everyone
Classification and general
properties of textile fibres
1UNIT
Commercial GarmentTechnology78
needs to know about textiles as we use them in some way or the other. To
understand about textiles the study oftextiles willhelp to a great extent when
we buytextile materials this knowledge willprevent us frommaking mistakes
and we willbe able to purchase good qualitymaterials.
There is a growing demand for textilesand clothing bypeopleofallwalks
oflife.
Yarns are produced bytwisting or spinningofthe textile fibres and in turn
fabric is a structure produced byinterlacing or interloping ofthe yarns..
There are certain terms which are used very often in the studyoftextiles
that are to be understood first. Most ofthe fabrics we use for various purposes
are woven that means theyare constructed byinterlacing sets ofyarns that run
along lengthwise and crosswise directions. Each yarn is made up of several
fibres therefore it is essentialto know or to definethe terms like fibreyarns and
fabrics.
A “fibre “is defined as anyproduct capable of being woven or otherwise
madeinto fabric.It issmallest visibleunit oftextileproduct.Afibrecanbedefined
as a “pliable” hair like strand that is very small in diameter in relation to its
length”. Fibresarethefundamentalunitsorthebuildingblocksusedinthemaking
oftextile yarns and fabrics.
Fibres arethefundamentalunitsusedinmaking oftextileyarnsand later on
into fabric. Thus fibres are the essentialcomponents and basic units and are an
essentialcomponents for making yarns. These fibres areofmanytypes.
Definition ofYarns
Fabricsmadeout ofdifferent fibresareavailableinthemarket. Thecommon
fibres that are used for fabrics are obtained from different sources. There are
few fibres which are naturally available. Still some fibres are synthetised by
usingchemicalsand are knownassynthetic fibreseg. Nylonpolyster and acrylic
fibres.
Some fibresare manufactured byusing raw materialfromnatureand they
are termed as man made fibres. Eg: Rayon, Polynosic, azlon etc.
1.1 Classification of textile fibres
Let us see how fibres are classified
According to the source from which textile fibres are obtained fibres are
broadlyclassified into two ways.
Paper - II Textile Science 79
Vegetable fibres or cellulosic fibres
The fibres that are derived from plants are called vegetable fibres. The
basic materialofallplant life iscellulose. Cellulose is made upofelements like
carbon, hydrogen and oxygen. These cellulose fibres have certain common
properties like low resilience, high density, and good conductor ofheat. They
are highlyabsorbent and are resistant to high temperature. Cotton flax, jute,
ramie are some ofthe examples ofvegetable fibres.
Animal fibres
The fibres which are obtained fromanimals are called animalfibres. Wool
and silk are common examples ofanimalfibres. They are made up of protein
molecules. The basic elements in the protein molecules are carbon, hydrogen,
oxygen and nitrogen. Animal fibres have high resiliency but weak when wet
because theyare bad conductors ofheat.
Mineral fibres
Theyare the inorganic materials shaped into fibres and aremainlyused in
the fire prooffabrics.Asbestos is the example ofmineralfibre. Mineralfibres
are fire proof, resistant to acids and are used forindustrialpurposes.
Vegetable
Eg. Cotton
Linen
Kapok
Jute
Hemp
Animal
Eg. Silk
wool
Mineral
Eg.
Asbestos
Regenerated
Cellulose
Eg. Nitro
cellulose rayon
2. Cupram-
monium
3. Viscose
Rayon
Synthetics
Eg.
polyester,
Nylon,
Acrylic
Acetate
Cellu-
lose
Eg.Nylon
Natural Manmade
Fibres
Commercial GarmentTechnology80
Man made fibres
These refer to those fibres that are not naturallypresent innature and are
made artificiallybyman. Manmadefibres have highstrength, strong when wet
lowmoistureabsorptioncharacteristics. Examplesofmanmadefibresareviscose
rayon, acetate rayon, nylon, polyester etc. Depending onraw materialchosen
for making ofthe fibres theyareclassified as cellulosic fibres, proteinfibres and
synthetic fibres.
1.2 General properties of textile fibres
1. Staple Fibres
Natural or man made or short length fibres which measures in inches or
fractionofinchexample 3/4 inch to 18 inchesexcept silk allother naturalfibres
are staple fibres. Staple fibres are oflimited length.
2. Filament
Long continuous fibres strands ofindefinite length measured in yards or
meters fibres of continuous length long enough to be used in fabric as such
Naturalsilkfilament is 360-1200 meters. Synthetic filaments canbemade many
kilometers long. The onlynaturalfibre available is silk.
3. Texture
It isthe tactile sensationexperienced when hand is passed over a surface.
Staple fibres and fabrics made fromstaple are lightlyroughwhile filaments and
fabrics made fromfilaments fibres are smooth..
4. Resilience
It means that when fibre is compressed and later when the pressure is
released. It willtend to returnto its originalshape. Resistance to compression
varies fromfibre to fibre.
This qualitycauses the fabric to be wrinkle resistant with the resistance
varying according to the degree of elasticity inherent in the fibre. Wool has
outstanding resiliencywhile it is poorincotton.
5. Luster
It isseenwhenlight reflected fromasurface. It is moresubdued thanshine.
Silk andsynthetics have luster thancellulosic fibres. Infact syntheticshave high
luster whichispurposefullyremoved during spinning.
Paper - II Textile Science 81
6. Static Electricity
It is generated bythe frictionofa fabric when it is rubbed against itselfor
other objects. If the electricalcharge that is not conducted away, It tends to
build up onthe surface and whenfabriccomesincontact witha good conductor
a shock or transfer occurs. This transfer maysometimesproduce sparks. This
is morefeelduring hot andhumid conditions.
7. Crimp
Woolfibre ismore or less wavyand has twists. Thiswaviness is termed
as crimp. Finerthewool morewillbethecrimpsinit. Marino woolwillhave30
crimps per inchwhile coarse woolhasonlyone or two. Thispropertyofhaving
crimps gives elasticityto the fibre.
8. Elasticity
It is the abilityofstretched material to return immediatelyto its original
size.
1.3 Difference between cellulose and synthetic fibres
Among natural fibres available cotton, wool and silk are the most
commonlyused fibres for making fabrics.Among artificialfibres rayon, nylon
and polyester are popular. The following are thedifferences betweenvegetable
fibres andsynthetic fibres.
Difference betweenvegetableand synthetic fibre
S.No
1.
2.
3.
4.
Cellulosic fibres
Lowresiliency:Fabricwrinklesunless
anyfinishingisgiven
Highwaterabsorbency:Comfortable
for summer wears, good for towel,
hand kerchiefand diapers.
Cellulosicfibresaregoodconductors
of heat.eg: Cotton is a better
conductor ofheat but less than that
ofrayon.
Identification: Cellulosefibres ignite
quickly, burns freelywithsmoke and
have an after glow and after burning
Synthetic fibres
High resiliency: Less wrinkles
after washing and wearing
Low moisture absorption:
Easilywashable and easyspot
removing.
Synthetic fibres are also good
conductors of heat they melt
withhotorironictouchwithhot
objects.
Identification:Readilyburnsand
melts giving a distinct plastic
burningodour.
Commercial GarmentTechnology82
Polyesterfibres burnreadilyandquicklywitha chemicalsmell. It continues
to burn after removing fromflame and gives a plastic like in crushable bleed.
Conclusion
Fabrics are made out of different fibres are available in the market. The
growth ofthe textile industryislargelythe work ofthe professionalpersonnel.
New fibres new fabrics and new finishes make new demands for understanding
the importance ofthe textile fabrics and their properties.
Test your understanding-I
State whether the following statements are true or false
1. Our primary needs are food, clothing and shelter (T / F)
2. Fibres are a pliable hair like structure (T / F)
3. Man made fibres are nylon and polyester (T / F)
4. Luster isthe naturaltendencyto returntheir originalcondition(T / F)
5. Static electricityis generated byfriction ofa fabric (T / F)
forms and a greyfeatheryash.
Cellulosic fibreshavehighaffinityfor
dyes.
Cellulosicfibres areresistant to moth
but less susceptibleto mildew hence
damp clothes should not be stored.
Cellulosic fibres need ironing at low
temperatures.Eg:wool
Susceptible to strong mineral and
organic acids stainsthat require acid
treatment should berapidlyremoved.
Synthetic fibres have low
affinityfor dyes.
Highly resistant to moths,
mildew and insects.
Synthetic fibresare adjusted
withhighheatsettings.Hence
it is good for embossed
designing and easy for plant
setting.
Synthetic fibres get readily
damaged due to acids.E.g.:
Nylon
5.
6.
7.
8.
Paper - II Textile Science 83
Test your understanding-2
State whetherthe following statements aretrue or false
1. Waviness is terms as crimp (T / F)
2. Examples ofnaturalfibres are polyester and nylon ( T / F)
3. Cottonis a cellulosic fibre (T / F)
4. Woolfabrics gives warmth (T / F)
5. Nylonis first synthetic fibre invented in 1930 (T / F)
Short Answer Type Questions
1. What are fibres ?
2. What are the examples ofvegetable fibres ?
3. What are animalfibres ?
4. What are mineralfibres ?
5. What are man-made fibres ?
6. What is filament ?
7. What is staple fibre ?
8. What is Resiliency?
9. Define Luster and static electricity?
10. Define Crimp ?
Long Answer Type Questions
1. Write the classification oftextile fibres ?
2. What are the generalproperties oftextile fibres ?
3. What arethe differences between cellulosic and synthetic fibres ?
Answers to Test your understanding - I
1. True
2. True
3. True
4. False-resilience
Commercial GarmentTechnology84
5. True.
Answers to Test your understanding - II
1. True
2. False-synthetic fibres-polyster, nylon
Naturalfibres-cotton,wool, silk
3. True
4. True
5. True
Structure
2.0Introduction
2.1 Manufacture ofhand made cottonin India
2.2 Manufacture ofmachine made cotton
2.3 ByProducts ofcotton
2.4 Properties ofcellulose fibre - cotton
2.5 Fabrics ofCotton
2.6 Finishes for cotton
2.7 Consumer demand for cotton
Learning Objectives
After studying the chapter you willbe able to:
• Understand the manufacturing ofcotton byhandand bymachine.
• Identifythe structure and compositionoffibre.
• Distinguish thevarious properties ofcottonthat is physical, thermal,
chemicaland biologicalproperties.
• Various characteristics ofcotton.
• Understand about cotton fibre blends.
Manufacture and Properties
of Cellulose Fibres - Cotton
2UNIT
Commercial GarmentTechnology86
• Know the consumer demand for cotton.
• Understand the major end use of cotton.
Unit Preview
Thisunitdealswiththemanufacturingprocessofcottonbyhandandmachine
made, byproducts ofcotton. Thevarious properties suchasphysical, chemical
and biologicalproperteisofcotton, and variousfinishes for cotton.
2.0 Introduction
Cotton is obtainedplant source and it is classified as a naturalmaterialas it
is obtained from the seeds of cellulose seed fibre staple fibre measuring 10-
65mm in length and white to beige in color inits natural state. It is composed
basically of a substance called cellulose. As cotton occupies 50% of the
consumption offibres byweight inthe world it iscalled as the kingofallfibres.
Cotton is the fabric for every home and is the most widely produced of
textile fabrics today. It has now beenproved that India was thefirst countryto
manufacture cotton.Among the recent findings at Mohenjo-Daro were a few
scrapes ofcottonsticking to theside ofa sliversvase. Cottonis thewhite downy
covering ofthe seed grown in the pods. The cotton plant grownin the tropics
needs a climate with 6 months of summer weather to blossom and produce
pods.
Fig. 2.1 Cotton Boll
Paper - II Textile Science 87
The cottonfibreis the shortest ofallthe textile fibres. Itslengthvaries from
8/10 ofaninchto 2 inches. Cottonwith short lengthfibresis technicallyknown
as “short staple”. The onewiththe long fibresis called “long staple”and it more
used since it is used for makingfine qualities ofcloth. Long staple is especially
suitable asit is easyto spinand produces astrong smoothyarn. Itis also suitable
for mercerizationa finishing process used to improvethe absorbency, strength
and lusteroffibre.
Cultivation of cotton
Theprincipalcottonproducing regions are Egypt, southernUnited States,
India, BrazilthewesternandsoutherncostofAmericaandEastIndies. It requires
200 daysto continue warmweatherwith adequate moisture andsunlight. Frost
is harmfulto the plant. MarchandAprilmonths are suitable for plantation.
Americaproducesmorethan40%oftheworld’scotton. Indiarankssecond
to the United States as a producer and exporter ofcotton.
2.1 Manufacture of hand made cotton in India
The tools and appliances used bycotton weaves consist ofa spinning
wheel (charkha) and a spindle (takli). The cotton is the first ‘separated’ and
‘carded’. Abow shaped beater known as ‘dhun’is used for the purpose. The
string ofthe bow is placed on the cotton and is made to vibrate bymeans ofa
woodenhammer.These vibrations cleanses allforeignmatter such asseeds and
leaves leavingsoft finecottonbehind. The fine cottonisrolled onstick to forma
cylinder about halfa cubit (6 inches) long and halfan inch in diameter. This is
tied to a spindle or takli. The charkha wheel is turned and the thin thread is
gentlydrawnout untilit is about 300 yards longand rolled on acharkha which
is wound on to a bamboo reel. The yarn is sent to weaving unit where it is
woven into a cloth.
After weaving the cloth is calendared witha blunt beater to giveit a gloss
and to softenit. The cloth is then stamped, ticketed and made readyfor sale.
Commercial GarmentTechnology88
2.2 Manufacture of Machine made cotton
Preparation: Thefibres are first removedfromseeds inagin. Thisprocess
is called ginning. Everybit ofthe cotton fibre is used in the manufacture . The
fibre mass is then compressed into bales and shipped into spinning mills.
The short ends left on the seeds after the longer fabric. Fibres have been
removed are used in the production of rayon, plastics, dynamite and many
otherbyproducts,whicharethenusedintheproductionofseedoil,hydrogenated
fats, soaps and cosmetics.
Forming the laps: Inthe step dirt fromcottonfibre is removed and fibres
are made in to a soft rollor lap. Thenseverallaps are combined into one.
Carding: These fibres are drawn together to form a loose rope called
sliver.
Doubling: Slivers arecombined here for uniformity.
Combing: Thisprocessis continuationand refinement ofcarding process.
Allcotton yarns for fabrics are carded but not allare combed. Yarns that are
combed are finer evenand freefromallwoodystalkofthe plant. Theyare used
for finer quality fabrics such as voile and organdie. Fabrics made from these
fabrics are expensive too. The slivers are called carded slivers.
Drawing: The slivers is then combined, smoothened and stretched. The
sliversmaybe drawnreduced further insize andgivenaslight twistbyaprocess
Cotton pods
Ginning (RemovalofSeeds)
Lap Formation
Carding
Doubling --> Combing
Drawing
Roving
Spinning
Paper - II Textile Science 89
called roving in which the slivers is passed through rollers and wound on to
bobbins set into spindles. It is done ina speed frame.
Roving: Thebobbins areplaced ontherovingframewherefurtherdrawing
and twisting takesplace untilthe cottonstock is about a pencillead in diameter.
Spinning: Doneonthe spinning framewhere the stockpassesthroughsets
ofhighspeed rollers and gives the yarnofdesired thickness.
Weaving and dying:The yarn is then knitted or woven in anyone ofthe
varietyofweaves and structures. Warp yarns are usuallymorestronglytwisted
thanfillingyarnssincetheymustwithstandgreaterstraininweavingandfinishing.
Dye stuffs maybe applied to raw cotton, yarn or piece goods.
Finishing:Itincludesstarching,calendaring,sanforizing,mercerizing orother
finishes as it is necessaryfor the particulars use for which theclothis intended.
These finishes may be applied to yarns but are usually applied to fabric. The
fabrics maybe given these specialfinishes before or after dyeing.
2.3 By products of cotton
Cotton linters: Linters are short, fuzzy fibres that remain on the seeds
after theyhave beenseparated fromthe fibre inthe cotton gin. Theyareused in
the manufacturing ofrayonand acetates, plasticsand photographic film.
Fig. 2.2 Cross Section Fig. 2.3 Cotton Fibre under the microscope
Hulls: These are outside portion ofthe cotton seeds rich in nitrogen and
used as fertilizers, paper cattle feed.
Commercial GarmentTechnology90
Inner seed: It yields cotton seed oilwhichis used as cooking oils and in
the manufacturingofsoap.
2.4 Properties of cellulose fibre- cotton
1. Physical properties
a. Structure:Thecottonfibreisshort (1/2inch-2 longinch)andcylindrical
ortubularasit grows. Thecottonfibreisessentiallycelluloseconsistingofcarbon,
hydrogen and oxygen. Bleached cotton is almost pure cellulose raw cotton
contains about 5% ofimpurities.
b. Strength: Cottonfibre is relativelystrong which is due to the intricate
structure and70% crystalline.
c. Elasticity: Cottonisrelativelyinelasticbecauseofits crystallinepolymer
systemand for this reason cottontextile wrinkle and crease readily.
d. Hygroscopic moisture: Cottondoesnot hold moisture so wellas wool
or silk but absorbs it and so feels damp much more quickly. It also rapidly
spreadsthroughout the material.
e. Electricalproperty: Thehygroscopic nature ordinarily prevents cotton
textile materials fromdeveloping static electricity.
f.Absorbency:As cotton has cellulose it is a good absorbent offibre.
2. Thermal properties
Cotton fibres have the ability to conduct heat energy, minimizing any
destructive heat accumulationthus theycanwithstandhot ironing temperature.
Drap ability: Cotton does not have good body to drape well in shape.
The type ofconstructionofthe fabric mayimprove this property.
Resilience: Cotton wrinkles easilysome wrinkle resistant finishes may
reduce this property.
Cleanliness and wash ability: Though cotton absorbs dust due to its
rough nature. It canbe washed easilyin the hot water andstrong soaps without
damaging the fibre.
Lustre:Thenaturalcottonhas no pronouncedlustre. This canbeimproved
bythe mercerizationfinishofthe cotton(that issodiumhydroxide treatment).
Shrinkage: Thefibre itselfdoes not shrink but cottonfibrewhichhas been
stretched in the finishing process tends to relaxback creating shrinkage.
Paper - II Textile Science 91
Heat conductivity: Cotton is the better conductor ofheat than woolor
silk but not as good as rayon.
3. Chemical properties
Action of acids and alkalies
Strong acids willdestroythe fibres immediately. Diluteinorganic acids will
weakenthe fibre and ifleft drywillrot it. Therefore after treatment withacidic
solutions cottonarticles should be thoroughlyrinsed inwater. Theyare affected
verylittle byorganic acids. Theyarealso quite resistant to alkalisevento strong
caustic alkalies at hightemperature and pressure.
In 8% NaOH cotton fibres swells, spirals, twisted uncoiland shrinks and
become thicker. The resultant fibre issmoother, lustrous, and strongerand has
increased water and dye absorption.
Effect of bleaching: These have no effects until used in uncontrolled
conditions andwith heat.
Effect of sunlight and weather: Ultraviolet rays of sunlight affect the
strength offibre and change the colour to yellow whenexposed to prolonged
period. Pollution also effect fibre.Concentrated and diluted mineralacids like
sulphuric acids willdiscolour fibre .
Affinity to dyes: Cottontakes in dyes better than linen but not as readily
as silk and wool. If a mordant is used cotton is easy enough to dye mordant
colours, direct or substantive dyes should be applied to the cotton.
Effect of perspiration: Both acidic and alkaline perspiration discolours
the fibre.
4. Biological properties
Resistancetomicroorganisms:Themildewandbacteriadamagescotton.
Resistance to insects: Moths and beetles willnot affect or damage the
cotton. But the sliver fish eatsthe cotton cellulose.
2.5 Fabrics in cotton
Flannelette and flannel:Asoft napped cotton fabric its warmth in wear
is due to the fact that the nap traps a layer ofair between the bodyand the cold
outside. Incompositionit isthesameasordinarycotton,buttreatment inweaving
makes it veryinflammable. For this reasonattempts have beenmadeto make it
fireproof bysaturating the fibre with metallic salt, but ingeneralfire proofing
does not withstand washing.
Commercial GarmentTechnology92
Organdie: Athin light fabric in plain weave with a verystiff finish. It is
madefromgoodqualitycombedyarn. Theyarnis made fromlongstaple cotton
and is spunis withmanytwists. This along withthefinishing process produces
its characteristic transparent crispness. The aimis to give a permanent finish.
The fabric is used for summer and evening wear.
Muslin: This is a cool, very light, and plain weave cloth also used for
summer wear. The name derives fromthe city ofMosulwhere the fabric was
first made muslins wear not always plain, silk and even gold stripes woven in
whenmade inmosul but as cottonwas grownmore plentifullyand the women
could spinyarns ofgreat fineness, cotton yarns graduallysuper seeded silk.
2.6 Finishes for cotton
The resinandthenonresinfinishesgivethecottonsomeeasyand minimum
care features of as synthetics.Advances in antibacterial mildew resistant and
flame resistant treatmentshave improved the effectivenessofthe performances
ofcotton invarious end uses.
Regular finishes like singeing for smoothness mercerization for strength,
lurtre andaffinityfor dyes, sizing and calendaring for lustre, maximumstiffness
bodyand smoothness.Specialfinishlike sanforizing formaximumpre shinking,
crease resistant, antibacterialfinishes, mildew and rot treatment napping for
softness, warmth, absorbencyand mothrepellent treatment are common.
Fibre blends
Amongthevarioustypesofblendsavailableinmarkettodaypolyster, cotton
terycotton, silk, linencotton, viscose rayonandcotton and nylon.
Reasons of blending are:
To facilitate processing.
-To improve properties like dimensionalstability.
- To produce better performance.
- To improve textute, hand or feelappearanceoffabrics.
- To produce multicolor fabrics.
- To reduce cost.
2.7 Consumer demand for cotton
Versatality: Cottoncanserve for food (cottonseedproducts) forclothing
and for shelter. Cotton fibre canbe spun alone or it can be blended with other
Paper - II Textile Science 93
textile fibres such as linen, wool, silk, viscose rayon, polyster, nylon. It serves
the purpose of clothing or apparel, home furnishing and industrialfabrics by
giving comfort, durability, fashion and easefor care etc.
Durability: Due to naturaltwist cottonspinsso wellthat it canbe twisted
verytightly. Hence tightlytwisted yarnsproduce durable fabrics.
Comfort: Cottonconducts heat awayfromthe bodyand allowsthe cooler
temperature outside to reach the body, so it is a cool materialfor summer or
tropicalwear. Knitted cotton is used as comfortable wear.
Fashion rightness:Fashiondesigners ofvarious countrieshaveconsidered
cottonglamorousenoughto include intheir collections.
Ease ofcare: The factors oflight, laundering, ironingand perspirationare
commonconsideration incolor fastness to cotton.
Economy or price: Cotton materials are flexible to fit into all types of
economic group. Byproducts ofcottonare used for manypurposes.
Major end uses
Cotton is used forhome furnishing : Towels are most common as it is
highinabsorbency, wide range ofcolors, washabilityand durability. Sheets and
pillow cases aremostlyblends ofcottonwithpolyester or made ofpure cotton.
Drapes, curtains and upholsteryfabrics are made ofcotton and its blends.
Since cotton can be autoclaved at high temperatures, absorbency,
washability and low static build up are important factors for use of cotton in
hospitals.
Industrialuses includebook bindings, luggages, and handbags, shoes and,
slippers, tobacco cloth, woven wiping cloths as andwallcovering fabrics.
Wide range ofwearing apparels: blouses, shirts, dresses, childrenwear,
active wear, separatesswimwear, suits, jackets, skirts, pants, sweaters, hosiery,
bedspreads, comforters, throws,sheets, towels, tablecloths,tablemats, napkins.
Consumer Demand for Cotton
Versatality Economy Durability Comfort Fashion Ease of Care
Commercial GarmentTechnology94
Conclusion
Cotton continues to be the world’s major textile fibre despite of many
synthetics. It is the oldest and most versatile ofall fibres with good properties
when blended withother fabrics. The mainreason for use ofcottonis its good
weaving qualities, low cost, high absorption, excellent, abrasion, stability to
repeatedblending. Itcanbesafelyironedevenat hightemperatureof425degrees
F. It has excellent wash and wear and wrinkle resistance and also good ifresin
treated.
I. Test your understandings
State whether the following statement are true or false
1. Cotton does not have color retention property. ( T / F )
2. Cottoncannot be blended withother fibres. ( T / F )
3. Cotton conducts heat awayfromthe body. ( T / F )
4. Cottonis used for home furnishings. ( T / F )
5. Cottonis moth repellent and provides softness and warmth. ( T / F )
II. Test your understanding
State whether the statements are true or false
1. Cotton is naturalfibre. ( T / F )
2.The cottonwith short length fibre is called as short staple. ( T / F )
3. Hulls are inside portion ofcotton seeds. ( T / F )
4. Cotton is not good absorbent. ( T / F )
5. Cotton is a good conductor ofheat. ( T / F )
Short Answer Type Questions
1. What is staple?
2. Give the steps for recent advances in handmade sector?
3. What are the by products ofcotton?
4. What are physicalproperties ofcotton?
5. What are the uses ofcotton?
6. What are the reasons for fibre blends in cotton?
Paper - II Textile Science 95
Long Answer Type Questions
1. What are the chemicalproperties ofcotton?
2. What are the steps involved inpreparation ofmachine made cotton?
3. Write short notes onfollowing
(a) Kapok (b) Flannelette and flannel(c) Organdie
4. What are the characteristics ofcotton?
6. Write the consumer demand for cotton?
Answers for text yourunderstandings - I
1. False
2. False
3. True
4. True
5. True.
Answers for text your understandings - II
1. True
2. True
3. False-outside
4. False-due to cellulose fibre it is good absorbent.
5. True.
Commercial GarmentTechnology96
Structure
3.0Introduction
3.1 Historyofsilk
3.2 Productionof silk
3.3 Historyofwool
3.4 Manufacturingofwool
Learning Objectives
After studyingthis unit, you willbe able to
• Understand the varioustypes ofsilk.
• Explainthemanufacture ofsilk
• Describe the physicaland chemicalproperties ofsilk
• Explaintheclassificationofwool
• Understand manufacturingprocess ofwool.
• Explain the physicaland chemicalpropertiesofwool.
Unit Preview
Thisunitgivesustheinformationregardingthe manufactureofphysicaland
chemicalproperties ofprotein fibres.
Manufacture and Properties
of Protein Fibres
3UNIT
Paper - II Textile Science 97
(1) Silk (2) Wool
3.0 Introduction
Silkisconsideredas“Queenofalltextilefibres”asit hasbeautyandelegance
and good properties ofperformance. Silk is the naturalproteinfiber obtained
from silk worm cocoons. Japan is known for producing best variety of silk.
India produces different varieties of silk and is famous for hand woven silk
textiles. There is a tremendous silk production increase in recent years. The
production ofsilk is called Sericulture. To obtain qualityand quantity ofsilk
rearing conditionsare controlled carefullythroughoutthe life cycleofsilkmoth.
These are two types of silk mulberry or cultivated silk and wild silk.
Cultivated silk iscreamysilk white oryellowishwhite in color. White wild silk
color rangefrombrownish to goldenyellow incolor.
3.1 History of silk
Sericulture or silk production has a long and colorfulhistoryunknown to
most people. For centuries the west knewverylittle about silkand people who
made it pliny, the romanhistorianwrote inhis naturalhistoryin70 BC“silk was
obtained byremoving the down fromleaves withthe help ofwater”. For more
than 2000 years these Chinese kept the secret ofsilkaltogether to themselves.
According to legend the beginning ofhistoryofuse ofsilk as textile fibre goes
back to 260 BC. When fourteen year old wife ofChinese emperor Huang-Ti
discoveredthe secret ofdrawingthe filament fromcocoonofthe silk wormand
producingafabricfromthe filament.This youngprincess Si-ling-chiis knownas
‘godess ofsilk worms’and isthe centre ofreligiousceremonies connected with
the care ofsilk worms and the production ofsilk has long been an important
factor ineconomyofempire.
Silk has never lost its luxuryfieldappealand todayis shownbyallhouses
in their top fashion products some designers are working only on silk. It is
everywhere in fashionpicture. In intimate wearand outer wear, hand bags and
shoes.
3.2 Production of Silk
Silk worms feed on mulberry tree leaves and therefore for rearing them,
the growingofmulberry treesis the first essentialstep. These are grownbythe
agriculturists.
Silk worms havea short life ofonlyabout two monthsand during which
these pass through the following four stages1. Egg 2.wormor larvae 3. Pupa
and 4. moths.
Commercial GarmentTechnology98
Silk worms are made to lay eggs on specially prepared paper for this
purpose. Theeggscanbestored incoldstorageforsixweeks. Eggs arecollected
and kept at low temperature untiltheyare hatched. Eggs take tendays to hatch
Emerged caterpillars ofant head size are fed on fresh mulberryleaves.At this
stage the wormneeds specialcarebamboo trays with straw mats are provided
for them. Whenthe caterpillar is about eight weeks old it secretesaviscousfluid
fromtwo glandsonits head whichoozes out fromthe commonopening near its
mouth. The fluid is called ‘fibrion’.At the same time it also secretes a gummy
kind offluid called ‘sericin’whichpasses throughthe sameopening. The fibroin
gets hardened whenexposed to air. Thesilk wormspins around itselfto forma
cocoon. Thecocooncontains 2000 to 4000yards ofreelablesilk. Forseparating
thesilkthreadfromthe cocoons theyareimmersed inhot water.Thisimmersion
also kills the warminside. Thenthe cocoons are dries and stored.
Fig. 3.1Silk moth and eggs Fig. 3.2Larva ofItalianBombyx
mori silkworm moth
Fig. 3.3 Cocoon of Bombyxmori Fig. 3.4 Male Bombyxmori or mul-
berry-feeding silk wormmoth
Paper - II Textile Science 99
Reeling: Theprocess ofunwinding the filament fromthe cocoonis called
reeling. The care and skillin the reeling operation prevents defects in the raw
silk.Asthe filament ofsingle cocoonis too finefor commercialuse, threeto ten
strands are usuallyreeled at a timeto produce the desired diameter ofraw silk
thread. Several cocoons are placed in hot water to soften the gum and the
surfacesarebrushedlightlytofindtheendsthefilaments. Theseendsarecollected,
threaded througha guide and wound on to a wheelcalled ‘reel’.
Throwing:As thefibres are combined and pulled onto thereel, twist can
be inserted to hold the filaments together. This is called as throwing and the
resultingyarnis‘thrownyarn’. Thisyarnlatergoestoweavingorknittingindustry
based the type of yarn produced.
Spinning: Short ends ofsilk fibres fromthe outer and inner edges ofthe
cocoons and frombroken cocoons and spuninto yarns in a manner similar to
that usedfor cotton. This is called spun silk.
Degumming: Sericinor gumup to 30% ofthe weight ofthe silk fibre. It is
not usuallyremoveduntilafter the clothis wovenbecause servesas warp sizing
that protects theyarns frommechanicalinjuryduringweaving. Sericinremains
onthefibreduringreeling and throwingbeforefinishing, the gumis removed by
boiling the fabric in soap and water. The presence ofgumand sericinincreases
the tendencyfor the silk to water spots on fabrics when ironed.
Bleaching: Silkthread is treated with hydrogen peroxide.
Dyeing: Silk has great affinity for the dyes. Acid dyes produce brilliant
shades on silk.
Printing: Silk maybe left plainormaybeprinted byanymethodlike roller
printing, Screenprintingorblockprinting.Silksareusuallydriedandthenprinted.
Finishing: Silk fabricsrequire veryfew finishes becausetheyhave natural
lustre, softnessand drapability.
Weighting of silk: When silk is boiled to remove the excess of natural
gumorsericinit loosesweight. Thislossofweight isreplacedthroughtreatment
bymetals liketin, aluminiumetc inwater solutions. These arenot removed by
washing.
Weighted silk isnot durable because sunlight and perspirationweakens
fibres. Heavyweighting causes silk to crack.
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3.2.1 Various types of silk
Wild silk: Silkproduced bymoths ofspecies other than bombyxmori. It
is brown incolor more uneven and coarser. It is usuallycalled Tussar silk.
Waste silk orsilk noil: Short ends ofspunyarns or inblends with cotton
or wool. Sometimes it is called waste silk.
Dupion: Silk yarns made fromtwo cocoons that have beenformed in an
interlockedmanner.Theyarnisuneven,irregularandlargethanregularfilaments.
It isused inmaking shantungand duppioni.
Raw silk: Silk that has not had anydegumming.
Spun silk:Yarns made fromshort fibres frompierced cocoons and short
ends and outside and inside the edges ofcocoons.
3.2.2 Properties of silk
Microscopic structure
Silkhas itsuniqueproperties. It issoft, supple, strong lighterinweight than
anyothernaturalfibre. Silk is priced for itsweight. Silk is anaturalproteinfibre
where the protein fibroin is held bya gummysubstance .
Fig. 3.5 Microscopic structure of silk
Microscopic properties
Strength: Silk is the strongest naturalfibre. It has a tenacityof2.4 to 5.1
grams per denier. More over smoothness ofthe silk filament yarn reduces the
problemofwearfromabrasion. The strengthofthe spun silk yarns depends on
the lengthofsilk staple.
Paper - II Textile Science 101
Shape and appearance: Silk filaments are very fine and long. They
frequentlymeasure about 1000 to 1300 yards inlength. The widthofthe silk is
from9 to 11 microns.
Elasticity: It is an elastic fibre and its elasticityvaries as it is naturalfibre.
Silk fibre maybe stretched from1/7 to 1/5 its originallength before breaking.
Cultivated degummed silk viewed longitudinally under a microscopic,
resembles a smooth transparent rod under microscope. Silk in the gum has
rough irregular surface. Wild silk tend to be quite uneven and is some what
dark. It mayhave longitudinalstriations.
Resilience: Silkretains the shape and resists wrinkling rather well. This is
more in fabrics made frompure silk rather than spunsilk or weighted silk.
Drapabilty: Silk has a pliabilityandsuppleness’ that aided byits elasticity
and resilience givesit excellent drapability.
Heat conductivity: Since silk is a proteinfibre. It is a non conductor of
heat like wool. Hence it is used for winter apparel.
Absorbency:The good absorbtive propertyofsilk also contributes to its
effect inwarmer atmosphere. Silk generallyabsorbs about 11% ofits weight in
moisture whichmakes silk for easydying and printing.
Cleanliness andwashability: Silkis hygienicmaterialbecauseitssmooth
surface does not attract dirt. It canalso be easilycleaned bymild soapsand dry
cleaning.
Shrinkage: Dueto the filament inlength, smoothsurfacesilkhave normal
shrinkage which can be easilyrestored by ironing at moderate heat and damp
conditions.
Effect oflight: Continous exposureto light weakens silkfaster thaneither
cottonor wool.
Chemical properties
Resistance to mildew: Silk willnot be affected bymildew unless left for
time in damp state or under extreme conditions oftropicaldampness.
Reaction to alkalis: Silk is not as sensitive as wool to alkalis. It maybe
affected inconcentrationsand hightemperatures. Coldconcentrated solutions
ofalkalisuchas soda or causticpotashhas slight actiononsilk. Heated solution
dissolved silk.
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Reaction to acids: Concentratedmineralacids dissolve fasterthanwool.
Organicacidsdo not harmthemwhilemediumconcentrated HCL willdissolve
silk.
Affinityfordyes: Silkhasverygoodaffinityforaciddyes butlight fastness
isunsatisfactory.
Resistance to perspiration: Silk fabrics are damaged by perspiration.
The silk itselfgets deteriorated in the presence ofperspiration.
Reaction to bleach: Strong bleaches contain sodium hypochlorite will
deteriorate silk. Mild bleaches like sodium perborate and hydrogen peroxide
maybe used with normalcaution.
3.2.2 Uses of silk
Silk isanexpensive luxuryfabricusedformakingdifferent garments. Silkis
used primarilyin apparelandhome furnishing items becauseofits appearance
and cost. Silk is extremely versatile and can be used to create a variety of
fabrics fromsheer chiffons to heavybeautifulbrocades and velvets. Because of
silk absorbency it is appropriate for warm weather wear. Because of its low
conductivityit isusedforcoldweatherwear,also infurnishingsilkisoftenblended
with otherfibres to add soft luster for furnishing fabric. Occasionallyexpensive
hands made rugs are made fromsilk.
3.3 History of Wool
Woolhas the one ofthe first fibres to be converted into fabric. Woolfibre
grows from skin of sheep. It is composed of protein known as keratin. It is
crimp and has scales on its surface depending upon the breed of sheep. The
naturalproteinfibre consist ofamino acids. Woolhas 19 amino acids, keratin,
proteinandother organic acids.
Man uses woolas clothing in the veryearlystages ofhuman history. The
primitivemanisused it intheformofskinofcertainanimals to protectas wellas
to decorate his body. Man then discovered the use of hair of sheep after
interlocking and twisting themtogether under pressure and thus hair ofsheep
were used in making fabrics The interlocking of woolen fabrics is known as
felting.
Wool was probablyknown to the primitive man as he used sheep skin to
cover his bodyeven before the discoveryofother fibres.
Paper - II Textile Science 103
Woolis yellowishwhite fibre and has mediumluster. It isconsidered to be
weak fibre than manyother fibres however other properties suchas resiliency
and elasticitycompensatefor low strength.
3.3.1 Structure of wool
When the wool is fibre is untwisted it shows a kinky appearance. The
length varies from 1,1/2 to 18 inches, the long fibres are coarser than short
fibres.
Fig. 3.6 Microscopic structure ofWool
When observed under microscope the surface ofthe fibre seems to be
consisted to scales irregular ofshapeand slightlyoverlapping likescales offish.
3.3.2 Classification of wool
1. Merino wool: Merino sheep produce the best quality wool which is
originated fromSpain.
Classification by fleece
1. Lamb’s wool: The first fleece sheared from lamb about six to eight
months old is known as lambs wool. This is in fine qualityand soft texture.
2. Hogget wool: Woolobtained fromsheep of12 to 14 months old that
has not been previouslyshorn.
3. Pulled wool: When sheep is slaughtered for meat the wool is pulled
called as pulled wool.
4. Cotty wool: Verypoor grade wool.
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5. Wetherwool:Anyfleececlipped after the first shearing is called weter
wool.
3.4 Manufacturing of Wool
Shearing
Sheep are generallyshornoftheir fleeces inspring but thetime ofshearing
differs indifferent parts oftheworld. Machine clippers removethe fleece faster
and closer thanhand clippers. Superior woolvarietycomes fromthe sides and
shoulderswhereitgrowslonger, finerandsofteristreatedasgoodqualityfleece.
Wool fromthe chest ,bellyand shanks is treated as a second fleece.
Preparation
An average about 8 pounds of fleece is made from one sheep. Then the
fibers are packed in bags or bales. The raw wool or newly sheared fleece is
calledGrease woolbecauseit contains thenaturaloilofthesheep. WhenGreese
wool is washed, it loses from 20 to 80% of its original weight. The grease
known as yolk is widely used in the pharmaceutical industries for lanolin
compounds.
Sorting and grading
Skilledworkersdo woolsorting. Eachgradeis determined bytype, length,
fineness, elasticityand strength. Separating offibre bytouchand sight.
Scouring
Washing ofraw woolis analkaline solution is knownas scourcing. The
woolis treatedwithwarmwater, soap, mild solutionofsoda ashor other alkali
to remove dirt inthe fibres.
Iftherawwoolisnotsufficientlyclearof vegetable,substanceafterscouring
is put through the carbonizing bath. The fibres are then put through a dilute
solution ofsulphuric or hydrochloric acid which destroys anyvegetable. This
process is called as carbonizing and resultant woolis called ‘extract’.
To remove the Grease and dirt in raw wool it is put through a series of
naphtha balls followed by clear water to remove the naphtha. This is called
naphtalation. This process improves the dye uptake propertyofwool.
Garnetting
Recycled woolfibres are obtained byseparatelyreducing the unused and
used fibrous mass bya picking and shreddingprocess called garnetting.
Paper - II Textile Science 105
Drying:Woolis not allowed to become absolutelydryusuallyabout 12 to
16% ofmoisture is left inwoolto conditionit for subsequent handling.
Oiling:Aswoolis unmanageableafter scouring the fibreis usuallytreated
with various oils including animals, vegetable, mineral or a blend of these to
keep it frombeing becoming brittleo lubricate it for the spinning operation.
Dyeing: If the wool is to be dyed in raw stock it is dyed at this stage.
Some woolfabrics piece dyed, some are yarn or skin dyed and some are top
dyed.
Blending: Woolof different grades or pure wool fibres and other textile
fibers maybeblended mixedtogetherat thispoint.Alltheinformationshould be
present onthe labels.
Carding: Thecardingprocessintroduces theclassificationofwoolenyarns
andworsted yarns.It makesthe fibreparallelandsomeamount ofdirt isremoved
due to straightening of fibres. Fibres are used for the worsted yarn are more
straightened thanthe woolyarns.
Gelling and combing: The cardedwoolwhichis to bemade into worsted
yarnisput throughgillingandcombingoperations. Thegeillingprocessremoves
the shorter staple and straightens the fibre. This process removes short fibres
from1 to 4 inch lengthplaces the long fibre as parallelas possible and further
cleans the fibre byremoving any remaining loose impurities.
Drawing: Drawing is an advanced operation for worsted yarns which
doubles and redoubles slivers ofwoolfibres. The process draws, drafts, twists
andwindsthestockmakingsliversmorecompact andthinningtheminto slubbers.
Roving: This is the final stage before spinning roving is actually a light
twisting operationto hold thinslubbers intact.
Spinning:Inthespinningoperationthewoolrovingisdrawnoutandtwisted
into yarn. Woolen yarns are chiefly spun on the mule-Spinning machine are
worsted yarns arespunonanykindofspinning machine mule, ring, cap or flyer.
3.4.1 Properties of wool
Physical properties of wool
Strength: It is stronger thansilk. Whenwet woollooses about 25% ofits
strength. Longerthe fibre the greeter willbe the strengthofyarn.
Resiliency: Woolis highlyresilient and comes to its originalshape when
hanged afterwrinkled or created.
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Stretchability: Wool is highly elastic. It is about 10 to 30% stretched
when dry and 40 to 50% when wet upon receiving pressure upon drying it
readilyregainsitsoriginaldimensions.
Shrink ability: Woolis resistant shrinkage. However long exposure to
moisture maycause shrinkage.
Effect of friction: Frictionwillsoften the woolfibre especiallywhenwet
and thus isadvantageous inmaintaining smooth, soft texture offabrics.
Crimps: Woolfibre is more or less wavyand has twists. This waviness is
termed as‘crimp’. Finer the woolthe more willbethe crimps init. Merino wool
has 30 crimps per inch while coarse woolhas one or two.
Effect ofmoisture:Woolis the most hygroscopic in nature. It canabsorb
upto50%ofitsweightandcarryupto 20%weight, without giving thefeelingof
being wet. Upondrying it losses moisture slowlypreventing rapid evaporation
thusavoidingchillingfeelto theuser. It absorbsperspirationafterviolent exercise
and guards the bodyagainst suddenchange intemperature.
Heat conductivity: Woolfibre is a part is a poor conductor ofheat and
therefore thefabrics made fromthe fibre are considered most suitable as winter
wear.
Felting:Woolfibresinterlockandcontract whenexposedto heat, moisture,
and pressure. The scale like exterior of the fibres contributes to felting. The
fibres get softenedinweak alkaline solutionsdue to expansionofscales at their
free edges, withfriction and pressure theyagain interlock to forma felt. This
property is used in making felts for hats, shoes, floor-coverings and sound
proofingpurposes.
Effect of heat: Low heat has no effect but strong heat weakens the fibre
and destroys the colour ofthe fibre.
Chemical properties
Actionofacids:Diluteacidshavelittleeffect but eitherhotorconcentrated
acids weaken or dissolve the woolfibres.
Action of alkalis: Alkalis tend to make while wool yellowish, strong
solutionsofsodiumcarbonatewhenheateddestroys thefibre sodiumhydroxide
ishighlyinjurioustothewoolfibre.Howeverboraxandammoniahavenoharmful
influenceonwool.
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Action of bleaching agents: Strong bleaching agents like hypochlorite
have harmfuleffects on wool., potassiumpermanganate, sodiumperoxide and
hydrogenperoxidehowever cansafelybeused for bleaching andstainremoval.
Effects of moth and mildew : Wool is easilydamaged by moths that is
whyduringstorageofwoolengarmentsspecialcaseisneeded.Howevermildews
donot effects garments.
Finishesgiventowool:Felting,fulling, mothproofing,crabbing, decanting,
londonshrinking, napping, singeing and steaming.
Wool blends: Woolpolyster, woolacrylic, woolnylon, silk and wool.
3.4.2 Uses of wool
The majorityofwool(72.8%) is used in apparel, home furnishing account
for 15-45%, industrialuses 6 to 7% and exports 5%, woolaccounts for 3.3%
ofallfibres for apparel.
The mostimportant useofwoolis forapparelcoats, jackets, suits, dresses,
skirts, slacksmade fromwovenfabricsofvarying weights andknitted fabrics’.
Allthese givesthe warmthgarments and withgood tailored look.
In the home furnishing area the major use of wool is in carpets and rugs
where woolis used more, cover to the carpets andwarmin the rugs. Blends of
different syntheticfibreswithwoolforsuitingmaterialsareincreasinglyimportant.
This result infabrics that are more appropriate inwarmer conditions. Polyester
is the most important fibre used inblending withwool.
Conclusion
Selection of a fibre, should be willing to payfor weaving quality. Agood
quality fibre (either silk or wool) is not cheap and priecs are tending to rise.
Blends offibres with man made and naturalfibres have grown in importance.
The consumer should read the percentage of each fibre and selling point on
label.
I. Test your understanding
State whetherthe following statements aretrue or false
1. Silk fibre is the longest ofallnaturalfibres. ( T / F )
2. Theprocess ofunwinding the filament fromthe cocoonis called as
spinning. ( T / F )
3. Silk has great affinityfor dyes.Acid dyes produce brilliant shades on
silk. ( T / F )
Commercial GarmentTechnology108
4. Wild silk has uneven structure and is some what dark compared to
cultivated silk. ( T / F )
5. Silk fabrics deteriorate and coloris also affected due to perspiration.
( T / F )
II. Test yourunderstanding-2
State whetherthe following statements aretrue or false
1. Gradeofwoolisdeterminedbytype, length, fineness,elasticityoflength
( T / F )
2. Washing ofraw woolinalkaline solution is knownas reeling. ( T / F )
3. Woolis non hygroscopic innature. ( T / F )
4. Woolfibres interlock and contract when exposed to heat moisture and
pressure. ( T / F )
5. Bleaching agents have no effect on wool. ( T / F )
6. Wool can be blended bypolster, acrylic, nylon etc.
Short Answer Type Questions
1. What is filament fibre?
2. What are the physical properties ofsilk?
3. What is the microscopic appearance of silk?
4. What are the uses of silk?
5. What is the microscopic appearance of wool?
6. Write theclassificationofwool?
7. What are the uses of wool?
8. What are the physical properties ofwool?
Long Answer Type Questions
1. What are the chemicalproperties ofsilk?
2. Write the process ofmanufacturing silk fibre?
3. What are the various types of silk?
4. How do you manufacture woolfibre?
Paper - II Textile Science 109
5. What are the chemicalproperties ofwool?Write any4 chemical
properties in detail?
Answer for test your understanding - I
1. True
2. False (reeling)
3. True
4. True
5. True .
Answer for test your understanding - II
1. True
2. False (scoring).
3. False
4. True
5. False (strong bleaching agents like hypochlorite haveeffect on wool.
6. True.
Commercial GarmentTechnology110
Structure
4.0Introduction
4.1 Rayon Fiber
4.2 Polyster Fiber
Learning Objectives
After studyingthis unit, you willbe able to;
• Understand the manufacturing process ofRayon
• Identifythe structureofrayon fiber.
• Describe thephysicaland chemicalproperties ofrayon
• State the uses ofthe rayon
• State the types ofpolyester yarn
• Understand the manufacturingprocess ofpolyester
• Explainthephysicaland chemicalproperties ofpolyester yarn
• Classifythe types ofrayon.
Manufactured Fibres
4UNIT
Paper - II Textile Science 111
Unit Preview
This unit givesus the informationregarding themanufacture andproperties
ofman-made fibers.
(1) Rayon
(2) Polyester.
4.0 Introduction
A rayon fiber was the first man-made composed of pure cellulose the
substance ofwhichis themanconstituentofcellwallsoftreesandcotton. Rayon
fibers are made from cellulose that has been reformed or regenerated.
Consequently, these fibers are identified as “regenerated cellulose fibers”.
Because ofits lustre and soft hand feel, it resembledsilk and came to be known
as “artificialsilk”. However it ismore like cottoninits chemicalcomposition
4.1 Rayon
History of Rayon
Robert Hooke, theEnglish naturalist, had prophesied the production ofa
fibersuchasrayon, thefirstofthe manmadefiberslongago in1664. Hebelieved
thatitwaspossibleto makean“artificialglutinouscomposition”muchresembling,
if not fully like silk worm secretion George Audemars, a Swiss chemist,
discovered howto make cellulose nitrate. In1884, count Hilairede chardonnet
produced the first man made textile fibersfromnitro cellulose. He is known as
“father of Rayon”.
Wood Rayonis produced in manyways. Viscose Rayonis popular among
customers. It is made frompulp and cottonlinters. The otheris cellulose rayon
(acetate rayon) in the chemist terminology, rayon and acetate arenot synthetic
because natural materials- cotton, linters and wood pulp are used in their
manufacture, ratherthanchemicalelements.
4.1.1 Source of Rayon
Rayon is an artificial, man-made or synthetic fibre made from cellulose.
Commercially rayon was produced about 48 years back. Rayon produced at
that timewas verylustrous theywere given this name which means “reflecting
the raysofsun”.
Themainobjectiveinmanufacturingrayonwasto provideacheapsubstitute
for silk. India has been importing rayon fabrics and rayonyarn.
Commercial GarmentTechnology112
4.1.2 Structure orRayon
When seen under microscope, the fiber appears smooth and rounded.
Viscoserayonfibersarerodlikewithnumerous,longitudinal, threadlikestriations
or lines. These are due to the indentations offiber surface.
Fig. 4.1 Microscopic structure of Viscose Rayon
4.1.3 Manufacture of Rayons
All types of rayon are made from cellulose. There are main four main
procedures bywhichcellulose is transformed into rayon. Theyare
(1) Thenitrocellulose process
(2) Thecuprammoniumprocess
(3) The viscose process
(4) Thecellulose acetate process.
The generalprinciplesofrayonyarnproductioninvolvethefollowing steps.
(a)To treat cellulosechemicallyfor rendering fromit a liquid
(b)To force theliquidthroughfine holes
(c)To changefromliquid streaminto solid cellulose filaments.
The Viscose Process
This is discovered in 1892 in England. In this process Spruce, a type of
treechipsareused. Sprucelogsarereducedtowoodpulpandpurifiedforcellulose
base. Wood pulpistreatedwithcausticsoda to formalkalicellulose. It is treated
with carbon disulphide to form cellulose xanthate. This is dissolved in dilute
Paper - II Textile Science 113
caustic soda solution.Areddishor orangeliquid is formed. Thisliquid is filtered
and then kept for ageing untila thick fluid is formed whichis called ‘Viscose’.
This fluidisforcedthroughfinejets into a dilutesolutionofsulphuricacid. Inthis
waycellulose is regenerated into continuous fibers.
The largest production of rayon today is manufactured by this process.
The cost is low.
4.1.4 Properties of Rayon Fabrics
The development ofman-made fibers possessing along withthe prized
qualities ofthenaturalfiber is a tributeto humaningenuity.
Characteristics of Rayon Fabric
· HighlyAbsorbent
· Soft and comfortable
· Easyto dye
· Drapes well
Physical Properties
Strength :Thetensile strengthofviscoserayonis greaterthanthat ofwool
but is onlyhalfas great as silk. Viscose rayonis also weaker thancottonand its
strengthis reducedto 40 to 70percent whenwet.Yet it produces fairlydurable,
economical and serviceable fabric whose smoothness of surface favorably
withstands withfrictionofwear
Elasticity : Viscose rayonhas greater elasticitythan cottonbut less than
wool and silk. While viscose rayon fabrics have some inherent extensibility,
undue strainmight cause themto sag or even burst.
Cellulose
Steeping
Dissolving
Xanthation
Filtration
Extrusion
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Resilience : Viscose rayonlacks the resilience. It should be remembered
that the resistance ofa fabric to creasing depends on the kind of yarn, weave
and finishing process.
Drapability : Viscose rayon possesses a marked quality of drapability
because it is relativelyheavyweight fabric.
Heat Conductivity : Viscose rayon is a good conductor of heat and is
therefore appropriate forsummer clothing like cotton.
Absorbency :Viscose rayon is one ofthe most absorbent ofalltextiles. It
is moreabsorbent than cotton or linen, but less thanwooland silk.
Cleanliness and Washability
Because of smoothness, Viscose rayon fiber helps to produce hygeinic
fabrics that shed dirt. Since Viscose rayons temporarilylooses strength when
wet, it must be handled withcare when washed.
Reaction to Bleaches : Household bleaches containing sodium hypo
chlorite, sodiumperborateor hydrogen peroxide maybe safelyused.
Shrinkage :Viscose rayonfabrics tend to shrink morethancottonfabrics.
SpunViscose rayon fabrics shrink more, which can be givena shrink resistant
finish, suchas Sanforset.
Effect ofHeat :Viscoserayonis purecellulose fiber whichburnsas cotton.
Whenironing, onlymoderatelyhot temperature must be used.
Chemical Properties
Resistance to Mildew : Like cotton, Viscose rayon have tendency to
mildew. Suchfabrics should not beallowed to remainindamp conditions.
Reaction to Alkaline : Concentrated solutions of alkalies disintegrate
Viscose rayon.Amild soap withlukewarmwater is recommended in washing
rayons.
Reaction toAcids : Beingpure cellulose, thefabric is disintegratedbyhot
dilute and coldconcentrated acids similar to that ofcotton.
Affinity of Dyes : Viscose rayon fabrics absorb dye evenly and can be
dyed with a varietyofdyes, like acid, chrome, and disperse.
Resistance to Perspiration : It is fairly resistant to deterioration from
perspiration.
Paper - II Textile Science 115
4.1.5 Uses of Rayon Fiber
Apparel:Accessories, blouses, dresses, jackets, lingerie, linings, millinery,
slacks, sports shirt, sportswear, suit, ties, work clothes.
Home Furnishings : Bed spreads, blankets, curtains, draperies, sheets,
slipcovers, tableclothes, upholstery.
Industrial Uses : Industrial products, medical products, non-woven
products.
Other Uses : Feminine hygiene products.
It’s used inindustrialwipes, medicalsupplies, including bandages, diapers,
sanitarynapkin, andtampons in non-woven fabrics.
4.2 Polyester Fiber
Polyester is a synthetic fiber invented in 1941. The first polyester fiber is
known as‘Dacron’inAmerica and ‘Terylene’inBritain. Latervarious types of
polyesters are produced. Terylene fiber is made by synthesizing terephthalic
acid and ethylene glycol.
The ground work for development of polyester fiber is done by W.H.
Carothers. Polyester fiber is the long chain polymer produced from elements
derived fromcoal, air, water andpetroleum. Polyester is a thermoplastic fiber
and has good strength. It melts in flame and forms a grey hard non-crushable
bead. It is an easy care fabric and can be easily washed.
Polyesterfiberlooks like asmooth,glassrod similarto Nylon. Ifdelustered
it shows black spotted appearance. The length, width, shape and luster of the
polyester fibers arecontrolled during manufacture to suit a specific enduse. It is
mostlyblended with other fibers to improve its absorbencyandto lower static
electricity.
4.2.1 Method of Manufacture
Generally each companyproduces its own varietyof polyester through
there are likelymodifications under specific trademarks.
Eg : PET (Principle raw materialis ethylene diamine and terepthalic acid)
obtained frpmpetroleumand PCDT polyester.
Spinning ofFiber
Themoltenpolymerisrigourouslymaintainedatairtightcondition, asoxygen
willaffect its stability. The viscous melt is extruded throughspinneret, and the
Commercial GarmentTechnology116
filaments are subsequently drawn into desired polyester fiber. Variations in
production process depends on desired end results.
Fig. 4.2 Flow chart of manufacturing process ofpolyester
The holesofspinneret mayberound or modified to be trilobal, pentagonal,
hexagonal or octagonal shapes so as achieve specific effects such a greater
cushioningand insulativeproperties. Other properties maybeobtained withthe
aid ofspecific additives givento the spinning solution.
Upon extrusionofspinneret, the polyester filament does not have allthe
desired characteristics because ofrandomarrangement ofpolymer molecules.
The fibers are therefore drawn or elongated with the aid ofgodet wheels. The
temperature conditions andthe extent to whichthe fibers are drawnto 5 times
theiroriginallength.
Types of PolyesterYarn
The diameterofthe polyester yarnis determined by;
(a)The rateextrusionoffilaments fromthe spinneret.
(b)The number ofspinneret holes and therefore thenumber offilaments
Paper - II Textile Science 117
(c)The rate of drawing of filaments. The yarn comes in a wide range of
diameterand staplelengths. The yarnsare producedbasically, as monofilament,
multifilament and spunand sometimes the textured yarnsare also produced.
4.2.2 Properties of Polyester Fabrics
Properties of Polyester
· It resistswrinkling.
· It is easyto launder
· It dries quickly
· It’s resistantto stretching.
Physical Properties
Shape andAppearance : These fibers are generallyround and uniform.
The fiber is partiallytransparent andwhite to slightlyoff-white incolour.
Strength :The PETpolyesters are ingeneral, stronger. Polyester is found
in industrialuses and the highlydurable fabrics.
Elasticity : Polyesterfibers do not havehighdegree ofelasticity.Ingeneral
polyester fiber is characterized as having a high degree ofstretch resistance,
which means that polyester fabrics are not likely to stretch out of shape too
easily.
Resilience : Polyester fibers have high degree ofresilience. Not onlydoes
a polyester fabric resist wrinkling whendry, it also resists wrinkling whenwet.
Drapability:Fabricsofpolyesterfilament havesatisfactorydrapingquality.
Polyester spunyarn is flexible andsofter, therebydraping qualityis improved.
Heat Conductivity : Fabricsofpolyester filament aregoodconductors of
heat. Polyesterstapledoes not providegreater insulationintheyarnsandfabrics.
One ofthereasonfor apparelgreaterwarmthofpolyester isits low absorbency.
Absorbency : Polyester is one of the least absorbent fibers. This low
absorbencyhasimportant advantages- theywilldryveryfast, suited for water
repellent purposes, such as rain wear and theydo not stain easily.
Dimensional Stability : If the polyester is properly heat set, it will not
shrink, norstretchwhen subjected to boiling water, boiling cleaningsolvents or
ironing temperaturesthat are lower thanheat setting temperatures.
Commercial GarmentTechnology118
Shrinkage : Polyester fabricsshrinks as muchas20 %duringwet-finishing
operationsandtheyare generallyheatset inlater treatments.Theyhaveexcellent
dimensionalstability.
CleanlinessandWashability:Sincepolyesterfibersaregenerallysmooth,
has low absorbency, manystains lie onsurface, and are easilywashed, byhand
or machine but oilstains are veryhard to remove.
Chemical Properties
Reaction to Alkalies : At room temperature, polyesters has good
resistance to weak alkalies and fair resistance to strong alkali. It reduces with
increase intemperatureand alkalies concentration.
Reaction toAcids : Depending upontype, polyester has good resistance
to mineralandorganicacids. Highlyconcentrated solutionsat hightemperatures
cause degradation.
Eg:SulphuricAcid.
Effects of Bleaches: Fabricsofpolyestermaybe safelybleached, because
polyesters have good resistance to deterioration to household bleaches. Ifthe
polyester have opticalbrightener, bleaching is not necessary.
Effect of Heat: Ironing should be done at low temperature. It gets sticky
at 4400
F.
Effect of Light : Polyesterhas goodresistance to degradationbysunlight.
Over prolonged use, gradualdeteriorationoffiber occurs.
Affinity for Dyes : Polyesters are dyed with appropriate disperse,
developed dyes at high temperatures producing a good range of shades and
color fastness.
Resistance to Perspiration : Polyesters has no loss of strength from
continued contact witheither acid oralkaline perspiration.
PolyesterBlends: Polyestercottonblend, polyesterwoolblend, polyester
rayon, polyester silk blend, polyacetate blend, , polyester and nylon are some
common blends.
4.2.3 Uses of Polyester
The most important uses of the polyester is in “woven fabrics”. The
blended fabrics areattractive, durable and comfortable, retain their appearance
welland easycare. The first use of staple polyester was in tropicalsuiting for
men’s summersuits. The suits werelight inweight andmachine washable.
Paper - II Textile Science 119
Polyester and polyester blends are also used in home-furnishings, sheets,
blankets, bed spreads, curtains that match bed spreads, mattress ticking, table
clothes. They are used in upholstery fabrics; polyester carpets have a softer
hand thannylon carpets. Spun yarnare used in knitted fabrics. Here polyester
with cottonblends are used.
The other important use where it is used is as fiber fill. Used in pillows,
comforters, bedspreads, other quilted households and apparels, winter jackets
etc.
Non-woven fabric are the fourthimportant use ofthe polyesterfabrics eg:
fusible interfacings, pillowcovers, matress interlining etc.
It has many industrial uses too in pile fabrics, tents, ropes, cording,
fishing line , cover stock for disposable diapers, gardenhoses, sails, seat belts,
filter fabricsused inroad buildings, fertilizer bags, inmedicinalfield for artificial
arteries, veins and hearts.
Conclusion
Consumersaremostlyawareofthefibercontent withfibresandtheirblends.
The man-madefibres likerayon, polyesterto have qualitiesofstability, durability,
comfort, wrinkle resistance ease ofcare etc.
I. Test your understanding
State whetherfollowing statements areTrueor False.
(1) Rayon is the first man-made fibres made fromcellulose. (T / F)
(2) Acetate rayons are rod-like with no striations. (T / F)
(3) Nitrocellulose processis first used for productionofrayon fabrics.
(T / F)
(4) The largest production ofrayon is donebycuprammoniumprocess.
(T / F)
(5) Viscose rayon tend to shrink more than cotton fibers.(T / F)
II. Test your understanding
State whetherthe following statements areTrue or False
(1) Diameter ofpolyester yarn is determined byextrusionoffilaments of
spinneret, no. offilaments and rate ofdrawing filaments. (T / F)
(2) Polyester fabrics are bad conductors ofheat. (T / F)
Commercial GarmentTechnology120
(3) Polyesters is used for the water repellent purposes and willnot stain
easilydue to its hygroscopic nature. (T / F)
(4) Polyester is unaffected bymoths, carpet beetles, silver fishor other
insects. (T / F)
(5) Polyesterhas good resistance for degradation bysunlight. (T / F)
Short Answer Type Questions
(1) What is a man-made fiber? Who was the father ofrayon industry?
(2) What is the microscopic appearance ofrayon?
(3) What are the uses ofrayon?
(4) What are the physical properties ofrayon?
(5) What is the microscopic appearance ofpolyester?
(6) What are uses ofpolyester?
(7) What are the physicalproperties ofpolyester?
(8)Write the drapabilityin polyester fiber?
Long Answer Type Questions
(1) What are the chemical properties ofrayon?
(2) Write the manufacturing process ofrayonbyViscose process?
(3) What are the chemicalproperties ofpolyester?
(4) Write indetail, about manufacturing process ofpolyester fiber?
(5) Explain theuse ofpolyester?
Answer for test your understanding - I
(1)True
(2)False (cuprammoniumprocess)
(3)True
(4)False (Viscose process)
(5)True
Paper - II Textile Science 121
Answer for test your understanding - I
(1) True
(2) False
(3) False (due to low absorbency property)
(4) True
(5) True
Commercial GarmentTechnology122
Structure
5.0Introduction
5.1 Spinning andvarious types ofspinning
5.2Yarns andclassification ofyarns
Learning Objectives
After studying this unit, the student willbe able to
• Understand about the classification ofyarns.
• Know about end uses of plyyarns
• Know about end uses of corded yarns
• Know about noveltyyarns and types
• Understand yarn-twist.
• Explainthe yarncount and balance ofcloth.
Unit Preview
Thisunitgivesustheinformationregardingtheclassificationsofyarns, turst
in the yarns, balance ofcloth yarncount and noveltyyarns.
Spinning and Yarns
5UNIT
Paper - II Textile Science 123
5.0 Introduction
Spinningis theprocessofdrawingoutandtwistingofagroupor bundlesof
fibres into a continuous thread or yarn of sufficient strength to be woven or
knitted into fabrics.
In the beginningthe yarns were spunbymane withbarehands without the
aid of any tool and it must have been many centuries before the spindle was
evolved for spinning. The spindle or “takli”stillsurvives as a tool hand spinning
wool, silkand cotton yarn.
It isthe simplest toolwhichconsistsofa rounddisc whichis attachedinthe
center to a thin, smooth rod about inches long. The upper end ofthe rod has a
groove or a hook whichbulkofthe fibres, these are drawn out ina long stand.
The spinner while simultaneouslypulling thefibres, gives a twist to the spindle
and let it go. The spindle whirl around and thus twisting up the pulled fibres
makes a continuousthread. The thread is then wovenround therod above the
disc. The disc provides the necessary weight which quickens increases and
prolonged the revolving of the rod, therebythe twisting ofthe fibre ensures a
strong thread.
Who does not know the “charka” in India. Acharka is used for spinning
yarninthehandloomindustryinIndia. Theyarnspunonthecharkhaisofvarious
qualities.Thefamous“DaccaMuslins”whichwereuncomparablefortheirfineness
but alas are extinct now were wovenofa charka yarn. The inimitable soft and
light pashmina ofKashmir are stillwoven ofthe charkhaspin yarn.
Charkhas are ofvarious types. In the textile industries todayelectrically
driven machines are employed for spinning. Several machines are used to
complete theprocess ofspinning, whichconsists ofstages suchas drawing out
offibre to reduce size and to give slight twist-roving and then spinning. There
are two general methods ofprocedure. In one process, the action ofdrawing,
twisting and winding is continuous and this is called ‘ring’ spinning and in the
other, the drawingand twisting is stoppedwhile the twisted threadis wound up
(as inthe case ofhand spinning) and this is known as ‘mule spinning’. The ring
spinning is a quicker process andhas the advantage ofreducing operating cost
andincreaseproduction,but themulespunisfiner, softerandofgreaterevenness.
In spinning yarns, whether by hand or machine a difference has to be
made inthe yarn intended for warp and weft or filling. The warp yarnneeds a
greater amount oftwists to produce a strong firmthread which is used for the
foundationofthefabric. The yarnisgiventwistsofspecified numberofturns per
inch.At first, a continuous threador a strand is made fromfibres and severalof
these strands are twisted together to get a finalyarn.
Commercial GarmentTechnology124
Dependinguponthefibres, thepreparatorymethodsofspinningareclassified
into two types:
(1) Chemicalspinning– filament fibres
(2) Mechanicalspinning – for the short staple fibres
Types of Spinning
(1) Chemicalspinning
Chemicalspinningoperationsaregenerallyusedtomakeman-madefilament
fibers to yarns.Aviscous solution is extruded througha nozzle like die called a
spinneret. Man-made fibersare made into yarns bychemicalspinning.
There are three types ofchemicalspinning.
Theyare (1) Wet spinning
(2)Dryspinning
(3)Melt spinning
Wet Spinning
The first commercial method for manufacture of manmade fibre is wet
spinning ofcellulosic fibre-rayon. This process involves the use ofappropriate
liquid solutionwhich is pumped through smallnozzle called spinneret, into a
chemicalbaththat coagulatesthe extrudedsolutionofendlessstrandsoffilaments.
These coagulatedcontinuous fibers are drawnout ofbath, purifiedbywashing,
dried and thenwound onto spools. Theconstructionofspinneret decidesifit is
a mono-filament, if one hole, Multifilament if many holes are present in the
spinneret. The amount of twist givento the processed yarnwillaffect texture
andstrength.
DrySpinning
This processinvolves use offiberliquid solutionwhichispumped through
spinneret into an air chamber. The air reacts with extruded streams, of liquid
Chemical Spinning Mechanical Spinning
(filament fibres (Staple Fibres)
Wet Dry Melt Conventional Direct
Paper - II Textile Science 125
fiber causing them to solidify. These coagulated fibers are then drawn out of
chamber, twisted, or processed then wound onto spools.
Eg.Acetate
Melt spinning
Polyester chips obtained fromreacted chemicalcombinations are melted
and thenpumped through spinneret into an air chamber. The extruded stream
cools and solidifies into continuous filaments which are then drawn out from
chamber twisted or processed or subsequentlywounded onto spoons.
Eg. Polyester
(2) MechanicalSpinning
Mechanical spinning refers to a multistep procedure in which machines
physicallymanipulateandspinfibresintoyarns. Therearetwotypesofmechanical
spinning. Theyare(1) Conventionalspinning
(2) Direct spinning
Conventionalspinningis used to makeyarns fromnaturalstaplefibres and
some man-made fibers. It involves series ofmachine operations.
Direct spinning isused to produce staple yarnsfromfilament fibers.
Conventionalspinning
Basicallyconventionalspinning involves sorting andblending, formationof
web for ease ofhandling, alignment offibers, stretching offiber bundles and
actualspinning offibres into yarns.
Sorting and Blending
Picking
Carding
Drawing
Roving
Spinning
Combing
Commercial GarmentTechnology126
(1)Sorting and Blending: Thefirst stepinconventionalspinningofstaple
fibers issorting and blending. Balesoffibresare loosenedand fluffed. Impurities
such as dirt and leaves are removed and fibers are blended to product
specifications.
(2) Picking: It is thesecond step in conventionalspinning. The fibers are
formed into web like sheets for ease of handling. These fiber webs are called
laps. The forming ofstaple fibers into laps is called picking.
(3) Carding: Thefiber webisfedinto acarding machine,whichstraightens
the fibers andpartiallyarranges theminto parallelrows. Thealignedfiberwebis
thenformedinto along, untwistedropecalledasliver. Theprocess ofseparating
and aligning thefibers is called carding.
(4) Combing: Whenonlylong, smooth staple fibers aredesired the short
fibers are removed from the slivers in a combing machine. Removal of short
fibers and alignment of the remaining long fibers into parallel rows is called
combing.
(5)As only long fibers are used, combing increases luster and strength.
Thus a fabric composed of yarns than that have been combed will be more
expensive thana fabric composed ofyarns that have onlybeen carded.
(6) The drawing process uses four sets of rollers, each set rotating at
faster rate ofthe previous set severalsliverss are combined and pulled into one
long, thenslivers. Iffurther blendingisdesired, sliverss ofdifferent fibers maybe
combined inthe drawing process.
(7) In roving the drawnsliverss are pulled to approximatelyone fourth of
their originaldiameter and slight twist is added. Hence roving is process that
reduces thesliverss to a sizesuitable for spinning.
(8) There are three systems ofconventionalspinning a) cottonb) woolen
(c) worsted
Theyutilize thesteps previouslydiscussed. Here themachineryis designed
to handle specific type and lengthoffiber involved.
ConventionalSpinning
Cotton Woolen Worsted
eg. cotton, linen eg. wool and fur eg. long fibres
man made fibers fibres and staple with high
length man made degree turst
fibres
Paper - II Textile Science 127
Direct spinning
It is used to produce staple yarnsfromman-made filament fibers. It is less
expensive.Inthedirectspinning,weblikestructuresoffilamentfibersarestretched
and brokenat intervals producing long staple fibers. The staplefibers are then
drawn into sliverss. The remaining spinning process is done bythe following
steps.
5.2 Yarns and Classification of yarns
Yarns can be classified based on length of fibres present and number of
parts present.According to the lengthoffibres present in yarn.
Yarn are broadlyclassified as staple/spun, yarns or continuous filament
yarn. Spunyarn consist ofstaple fibre assembled and bound together bytwist
to producetherequired characteristicssuchasstrength, handle andappearance.
5.2.1 SpunYarns
Spunyarnsare made fromthestaple fibres that aretwisted together. Spun
yarnsarecharacterizedbyprotrudingfibreends. Spunyarnsstrengthisdependent
on the cohesive or the clinging power ofthe fibre and on the points ofcontact
Filament fibres stretched
Breaking
Drawing
Roving
Spinning
Spunyarn Filament yarn
Yarn
Smooth Textured
bulk
Napping Average
Twist
Voile
Twist
Crepe
Twist
Commercial GarmentTechnology128
resulting on pressure ofthe twist. Thegreater the number ofpoints ofcontact,
the greater is the resistance to the fibre slippage withinthe yarn.
Theyare suited to clothing fabric in which absorbency, bulk, warmth or
cotton like or wool like textures is desired. When worn fibre ends hold the
yarns awayfromclose contact fromthe skin, and so fabrics made ofspunyarn
is more comfortableona hot humid daythan a fabric ofsmoothfilament yarns.
Protruding ends contributeto a dullfuzzyappearance, to the sheddingoflit and
to theformationofpills onthe surface ofthefabric. Theyalso get dirted readily,
spun yarncanbe givendifferent types oftwist basedonthe end use as napping
twist.
Napping twist: This type ofyarn is called as low twist, yarn. It has 2.3
turns per inch such low twist results in lofty yarns which allow for napping of
fabric. Thus napped fabrics are bulky and provides warmth when used in
garments.
Average Twist: It is frequentlyused for yarns made ofstaplefibres and is
veryseldomusedfor filament yarns. Theamount oftwist that gives warp yarns
maximumstrengthis referred to asstandard warp twist.
Hard twist (Voile twist): When yarns are given 30-40 turns per inch,
theyarecalled hard/voile twisted yarns. The hardness ofthe yarn results when
twist brings fibres closer together and more compact.
CrepeYears: Crepe yarns aremade ofwitheither stapleor filament fibre.
Crepe is aFrenchword meaning crinkle. Theyare made with ahigh number of
turns per inch(40-80) inserted inyarns. This makes the yarnso livelyand kinky
that thetwist must be set before it canbewovenor knitted filament crepe yarns
are used in fabrics like Georgette and chiffon.
5.2.2 FilamentYarns
The range offilament yarns is as diverse as that ofstaple yarns. Filaments
yarns are divided into two types viz flat continuous filament and textured
continuousfilament yarn.
(a)Continuousfilamentyarnsareprovidedfromlongcontinuousfilaments.
Filaments yarns are primarilyman-made. Silk is the onlynaturalfilament and
accounts for less than 1% of the fibre and yarn production. Regular or
conventional filaments yarns are smooth and silk like as they come from the
spinneret. Their smoothnature gives themmore luster thanspunyarns, but the
luster varies withthe amount ofthedelusturing agent used inthe fibre spinning
solutionand theamount oftwist inthe yarn. Filament yarnshave no protruding
Paper - II Textile Science 129
ends, so theydo not shed lint; they resist pilling and fabrics made from them
tend to shed soileasily.
(b) Textured continuous yarn are man-made continuous filament yarns
that are been modified by subsequent processing to introduce crimps, coils,
loops or other distortions into the filament or with high twist or low twist. The
additionoftwist increases bulk texturing gives slipperyfilaments the aesthetic
propertyofspunyarns byalteringthe surface characteristics and creating space
between the fibres. It also improves the thermal and moisture absorption of
filament yarns.
According to the numberofparts inYarns
1. SimpleYarn.
Intheconstructionofsimpleyarn, onlyonekindoffibreisused. Themanner
inwhichthefibres are twistedwillbethesamethroughout the lengthofthe yarn.
Yarns are knownas simple, plyor cable depending uponthenumber ofstrands
theycontain.
2. SingleYarn
Inthis, anumberoffibresaretwistedtogetherinto acontinuouslength. The
yarns consists of one kind offibre. This type ofyarnis the oneusuallyfound in
most standard fabrics for clothing and householduse and purposes.
(a) Single yarn (b) Two ply yarn (c) Cord yarn
Fig. 5.1Types ofYarns
3. Ply yarn
Two or morethantwo single yarnsare twisted together to forma plyyarn.
These yarns areknown as multiple strand yarn. Iftwo single yarns are twisted
together, theresultingyarnisknownastwo-plyyarn. Ifthreearetwistedtogether
three-plyyarnand so-on.
Commercial GarmentTechnology130
4. Cord/Cable
It is made by a third twisted operation, in which ply yarns are twisted
together. Some types of sewing threads and some ropes belong to this group.
Cords are seldomused in apparelfabric, but used inindustrialweight fabrics.
Fig. 5.2 Parts ofYarn
DoubleYarn
This consists oftwo or more single strands treated as one in the weaving
process, but the strands are not twistedtogether. These areused for ornamental
effect as the low twist yarns produce luster and softness.
5.2.3 Novelty Yarns
The constructionofthese yarns is ofcomplexnature and is varied inmany
ways. These yarnsare usuallyplyyarnsofdifferent kindsoffibresor ofdifferent
colours and are irregular rather thansmooth single strand or yarn ofvarious
colours, sizesoffibres maybetwisted together to formcomplex yarn.Another
varietyisbrought about inthiskind ofyarnbyvarying the tensionorspeed after
intervals ofcertainlength. Thus allowing one part to loop or twist around the
other. Noveltyyarnsarealso constructedfromsimpleyarnbyvaryingtheamount
oftwist. The complextype ofnoveltyyarn is used withtwo objects inview one
is to combine different fibres eg. Cotton and rayon may be blended with or
covered bywoolor silk. This lowersthecost ofproduction. The other objective
is to producea noveltyyarn. Forthe construction ofnoveltyyarns, at least one
Binder
Ground
Effect
Paper - II Textile Science 131
or two single yarns are use. One forms the foundationyarn knownas a base or
the core and the other, The effect ofyarn whichis wound or looped round the
first one.Athird yarn called binder yarn is oftenused to fasten or tie the effect
yarn to the foundation yarn. These types ofyarns are mostlyused for drapery,
up hoisteryfabrics.
Fig. 5.3Parts of NoveltyYarn
5.2.4 Types of Novelty Yarns
Slubyarn: This is a yarn made withthick and thin placing byvarying the
amount oftwist in the yarn at regular intervals. Theyare found in draperyand
upholsteryfabrics.
Fig. 5.4 Slub yarn
Flock yarn: These are frequentlycalled as flake yarns. These are usually
single yarns inwhich smallamount offibres either different colours or luster or
bothareinserted into the yarnand held inplace bytwist ofbaseyarn eg: tweed
fabric. This gives a spotted and short streakyappearance.
Fig. 5.5 Flock yarn
Thick and thin yarns: These aresimilar to slubyarns but theseare made
fromfilament like slubprepared fromstaples. The pressure forcingthe spinning
solutionis varied the filament is thick in some places and thin insome.
Fig. 5.6Thick and thin yarn
Core yarn
Boucle yarn
Effect yarn
Commercial GarmentTechnology132
BoucleYarn: These are characterized by a projecting fromthe body of
the yarnat fairlyregular intervals. Thereare 3 plyyarns. Theeffect yarns forms
irregular waysurface and binder ties it to the base. It has twisted core yarn.
Fig. 5.7 BoucleYarn
Loop and curlyarn, Gimp yarn: Gimp is same as boucle but the effect
yarn isregular semicircular appearance, while in loop.
Snarl yarn or spike yarn: This is made in the same way as loop yarn
using ahighlytwisted effect yarn, whichforms snarls ratherthanloops.
Knop(button)yarn/knot/Nub/Spotyarn:Thisfeatureprominentbunches
ofone or more ofthe component yarn at regular or irregular intervals. This is
madeonaspecialmachine that permitsthe baseyarnto beheldalmost stationary
while the effect yarn is wrapped around it severaltimes to build upon enlarged
segment with brightlycoloured fibres added at the enlarged spot.
Fig. 5.8 Knopyarn
SeedorSplash: Theyresembleknops or knotyarnsbut theknot segments
are tinyinseed yarn and elongated in splash yarn.
Cloud: Atwo colouredyarn, inwhichbothyarns takeinturnto obscure or
cloud the other, giving the appearance ofanintermittent color change.
Spiral or Corkscrew : It is made bytwisting together two plyyarns that
differ insize, type or twist. These two parts maybe delivered to the twister at
different rates ofspeed.
Fig. 5.9 Spiral yarn
Boucle yarn
Paper - II Textile Science 133
Chenille Yarn: These create specialeffects chenille means caterpillar in
French. The yarn has a cut pile effect which is bound to the core on the loom
warps are arranged in groups (2-6) which are interlaced in a cross weaving
manner. Weft is inserted in a normal manner. These are cut into wrap way
threads.
Fig. 5.10 ChenilleYarn
MetallicYarn: These are primarilydecorative. The plastic coasting on it
resists tarnishing but care must be takenwhile pressing as puremetals are soft,
their thinfilms are used overa core yarnthat has replaced gold and slivers now.
There are two methods ofpressing.
Yarn twist: Twist isthe spiralarrangement ofthe fibres around theaxis of
theyarn.Revolvingoneendofthefibrestrandwhiletheotherendisheldstationary
produces twist.Twist binds the fibrestogether and gives thespunyarnstrength.
It isa wayto varythe appearance offabrics. The number oftwistsis referred to
as turns per inch. Theyhave a direct bearing onthe cost.
Twist is the spiralarrangement of the fibres around the axis of the yarn.
Revolving one endofthe fibre strand while the other end is held stationaryany
produces twist. Twist binds the fibres together and to gives the yarn. Higher
twist whichyields lower productivity.
Fig. 5.11Yarn twist
Direction of Twist
The direction of twist is described as s-twist and z-twist. Ayarn has S-
twist ifwhenheld ina verticalposition, the spiralconfirmthedirection ofslope
Commercial GarmentTechnology134
of the centralportion of the letter “Z”. Z-twist is the standard twist used for
weaving yarns. The majorityofsingleyarns are spunwithtwist in Z-direction.
TheAmount ofTwist varies with
1. The lengthoffibres
2. The size ofthe yarn
3. The intended use
5.2.5 Yarn count
Yarnnumber variesand it differsaccordingto the kind offibre. Manyyarns
are used for weaving and sewing threads are numbered bythe cotton system.
Spunyarnsize is referred to as count and isexpressed interms oflengthper unit
ofweight. It is anindirect system. The finer theyarn, the larger thenumber. The
count is basedonthe number ofhanks (1 hank is840 yards) in1pound ofyarn.
Inthissystemthe unit ofweight remains constant.
Count = length/ one pound.
Count = No of hanks x 840 yards / one pound.
Denier: Filament yarnsize is dependentlypart on the size ofthe holes in
the spinneret and partlyonthe rateat whichthe solutionispumped throughthe
spinneret and rate at whichit is withdrawn.
The sizeofthe filament yarns isdetermined as denier, whichis expressed in
terms ofweight per unit length. If9000 meters ofyarnweigh 1 gmit is then 1
denier. Inthissystem, the unit oflengthremains constant. The finertheyarn, the
smaller the number.
Denier = weight ofyarns ingms/9000 mts.
1 denier = 9000 mts weigh 1gm
Texsystem:The internationalorganizationforstandardizationhasadopted
theTexsystem, whichdetermines the yarncount or number inthesame wayfor
allfibre yarns and uses metric units.
Tex= weight in gms/100 mts ofyarn.
Conclusion
Therearedifferent typesofyarn.Eachhavingtheowncharacteristics. These
characteristics varyaccordingto the constructionand the treatment giveninthe
manufacture ofthe yarn. Yarns playa very important role in determining the
hand and performanceofthefabric.Yarnis the generic namefor the assemblage
Paper - II Textile Science 135
offibres that is laid downortwisted together. Thus yarns playanimportant role
inthetextileindustry.
I. Test your understanding
State whetherthe following statements aretrue or false
1. The threetypes ofspinning are wet, dryand melt spinning in chemical
spinning.
2. Dryspinning is used to make polyester.
3. The construction ofspinneret decides the diameter ofthefiber and the
type offibrei.e. mono filament and multifilament depending onnumber
ofholes.
4. Conventionalspinningutilizes the steps discussed for (a) Cotton
(b) Wool (c) Worsted fibers too.
5. Direct spinning is used to produce staple yarns fromnaturalfibres.
II. Test your understanding
State whether thefollowing statement areTrue/False
1. The warp yarn needs a greater amount oftwist to produce strong firm
thread (T/F).
2. Spunyarnconsists offilament fibres (T/F).
3. Napping can done to low-twist yarns. (T/F).
4. Crepe is French word meaning crinckle (T/F).
5. In simple yarn one kind offibre is used. (T/F).
6. Whentwo or more thantwo single yarns are twisted together,it is called
cable (T/F).
III. Test your understanding
State whether thefollowing statements areTrue/False
1. Noveltyyarnsare mostlyused for upholstery, drapery. (T/F)
2. Twist isthe spiralarrangement offibres around the axis ofthe yarn.
(T/F)
3. The direction ofthe twist is described as X-twist andY-twist. (T/F)
4. The count is based on number ofhanks in 1 pound of yarn. (T/F)
Commercial GarmentTechnology136
5. Denier –Weight ofyarns ingms/1000 mts (T/F).
Short Answer Type Questions
1. What is yarn?
2. What are spun yarn.
3. Write about continuous filament yarns.
4. Write about noveltyyarns.
5. What is yarn twist.
6. What is yarn count?
7. Write about tex system.
Long Answer Type Questions
1. Write the classification ofyarns.
2. What is filament yarn?Write about textured continuous yarns.
3. What are noveltyyarn?Write anyfour types ofnoveltyyarns.
Answers for test your understanding - I
(1)True
(2) False (acetate)
(3)True
(4)True
(5) False (man-made fibres)
Answers for test your understanding - II
1. True
2. False – Staple fibres
3. True
4. True
5. True
6. False – Ply yarn
Paper - II Textile Science 137
Answers for test your understanding - III
1. True
2. True
3. False – S & Z twists
4. True
5. False – 9000 mts.
4. Write indetailabout yarntwist.
Commercial GarmentTechnology138
Structure
6.0Introduction
6.1 Weaving
6.2Knitting
6.3 NonWoven fabrics
Learning Objectives
• Understand what is weaving
• Understand the generalcategories ofnonwovens a) durable b)
disposables
• Explainthesemidurable wovens.
• Know about a)Weft knitting b)Warp knitting
• Classificationofweft knit fabrics
• Design inweft knit fabrics
• Identificationofwarp knits.
Fabric Construction Methods
6UNIT
Paper - II Textile Science 139
Unit Preview
Thisunit givesus theinformationregarding thefabricconstructionmethods
such as
(a) Weaving
(b) Knitting
(c) Non woven fabrics.
6.0 Introduction
Fabrics are producedmostlyfromyarns. Few fabricsare directlyproduced
from fibers. In Indian market 70% of the fabrics are produced by weaving.
Amongtheotherfabricsthat isnonwovenfabricslacemakingisworthmentioning
along withneedle punched and tufted fabrics. Felts are fabrics made directly
fromfibers without making yarns where fusible use is mostlyemerging now a
day.
The fabric construction process determines the appearance and texture
the performance during use and care and cost of fabrics. The process often
determines the name ofthe fabric for eg: felt lace, double knitt and jersey. The
cost offabrics inrelation to the constructionprocess dependsuponthe number
of steps involved and the speed ofprocess, the fewer the steps the faster the
process, the cheaper is the fabric.
The fabric constructionmethods include weaving, knittingand nonwoven
fabrics.
6.1 Weaving
Yarn isturned into fabricsofgarments byweaving, knitting, or felting.
Fabrics are woveninlong lengths from40 to 100 or moreyards and from
about 20 to 60 inches in width. For a fabric to have strength and compactness
combined with a fair degree ofelasticity, the warp and filling threads must be
interlaced. This interlacing is called weavingand it is doneona loom.
An interlacing where the filling threads are passed alternatively over and
under thewarp threads is calledas a plainweave. It is the simplest ofallweaves.
Ifthe fillingsthreads are passedoneover and2 under ormore warp threads
willresult intwillfabrics.Thesurfaceofsuchfabrichaspatternofparalleldiagonal
ridges.
Commercial GarmentTechnology140
Ifthe warp threads or filling threads are considerablythicker then the rib-
weave is produced.
Thus the verylarge number of variations of methods for interlacing the
warp and filling threads makes to weave the wide variety of fabrics each of
which has specialproperties and uses.
The beam of the warp threads is placed at the back of the loom and the
threads are drawn from it across the loomfromback to front to be wound on
another roller. Forthe weaving ofplaincloth, the threads aredrawnthroughthe
eyes oftwo sets ofheddles.
The filling threads pass over and under alternate warp threads which are
lifted and loweredbythe corresponding heddles.
Toe cop with the filling threads is placed in a shuttle which is moved or
thrownfromside to sideacrossthe loom. Eachpassoftheshuttle laysonefilling
threads. Thecomblike reed describedearlierbeatsthefillingthreadstight against
thepreceedingfillthreads, asthefabricis wovenitis slowlywoundonto a roller
infront ofthe loom.
The following listsincludes some ofthemost commonweaves:
1. Plain weave (a) Rib weaves (b) Basket weave
2. Floating weave (a) Twillweave (b) Satin weave (c) Sateen weave.
And its variations
6.2 Knitting
The knittingsindustryisa uniqueanddistinct part ofthetextileindustry. It is
the second important method of making fabrics after weaving. The knit
characteristics are
• Bulkywithsurface effect.
• Looselyknittedor tightlyknitted.
• Rib-purl-tricot.
Circularknit:Anyfabric produced on acircular knitting machine.
Double knit:Aspecialtype ofribknit fabric usuallyclosedstitched witha
pattern or design effect, generallythicker, heavier and more stable than jersey.
Paper - II Textile Science 141
Difference betweenWeaving and Knitting
Weaving and knitting are the two most common process ofmaking cloth.
Weaving is the process of interlacing two sets of yarn at right angles. This
operation is done either on a hand or a power loom. Ifone set of yarns form
loops one loop caught into another and one row ofloops hanging on the one
below. The cloth is made byknitting.Of these two processes, Weaving is the
most common method although new and improved knitting machines make
clothquicklysatisfactoryand the attractive patterns.
Wales (in knitting’s): Aseriesofloops insuccessive rowslyinglengththe
wise ofthe fabric.
Purl: Purlis actuallythe opposite ofknit.
Fig. 6.1 Plain stich and purl stitch
Course: Aseries ofstitches or loops that run cross wise is knitted fabric,
corresponds to the fillings inwovengoods.
Stitch:Asingle loop or turnofthread oryarnmade byhandor machine in
sewing crocheting, tatting , lace making,knittingand knotting.
Jersey: Describes any knitted fabrics where in all of the stitches on one
side ofthe fabric are knit stitches, while allstitchesonthe reverse sideare either
purlstitches or a combination ofpurltuck and /or miss stitches also known as
singlestitches.
The knitting industryhas two mainbranches
(a) The knitted yarnsgoods industry : Whichproduces thefabric sold
to apparelmanufactures, sewing centre retailshops and others.
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(b) The knitted end produces products industry: Which produces
completed consumer products such as hosiery, sweaters, men’s T shirts and
athletic shirtsand others.
Weft knitting: Knits are classified as a) warp knits b) Weft knits.
It is a type of knitting in which yarns run horizontally from side to side
across the widthofthe fabrics.
The fabricis actuallyformed bymanipulating the knitting needlesto make
the loops in horizontal courses built one on top of another. All stitches in a
course are made byone yarn. It is simplest form;a weft knit canbe made from
one yarn.
Weft knits are made either flat or open width fabrics (like woven fabrics)
onso calledflat knitting machines.
Fig. 6.2 Simple warpknit fabric
Warp knitting:Warp knitting’sinvolvesthe preparationand useofa warp
beamcontaining averylarge number ofparallelyarns mounted on the knitting
machine. In warp knit fabrics the yarn run the length of the fabrics. The yarn
forms the verticalloop in the one course and theymove diagonallyto the next
wale to make a loop inthe following coarses. Theyarnzigzag fromsideto side
along thelengthofthe fabrics. Eachstitch ina coarse is made bydifferent yarn.
Knit fabrics names: Classical knit fabrics are named primarily on the
basis oftheir constructionnot onthe basis ofappearance and weight.
Identification ofwarp knits
Practicallyallthe warp knittedfabrics are identifiedanddistinguishedfrom
weft knitted materialsbycarefulobservation ofthe face and backofthe fabric
Paper - II Textile Science 143
usually with the aid of a pick glass. The face of the fabric has rather clearly
defined plainstitches. Generallyrunning verticallybut slightlyangled fromside
to side. The back of the fabric has slightlyangled but horizontal floats. These
floats are called ‘laps or under laps’ formed fromthe side ways movement of
the warp yarns as the fabric is made, the recognition oflaps ina knitted fabric
isthemost important distinguishing feature.
6.3 Non woven fabrics
Non wovenfabrics are made bythe anyprocess otherthanweaving. They
are defined as textile materials made directlyfrom fibers and held together as
fabrics bydifferent methods. The firstnonwovenwasintroducedin1942. There
are two generallycategories ofnon woven’s 1. Durable 2. Disposable.
Durable: The materials are not manufactured or intended to be thrown
awayafterthesingleorlimitednumberofapplications. Examplesincludeapparel
interlining, carpet backings etc.
Disposable: these materials are manufactured with the intention ofbeing
thrownawayafterthesingle orlimitednumberofapplications. Examplesinclude
disposable diapers, head rests, surgicalgowns, filters etc.
Semi durable non wovens: Some items might be considered as semi
durable like handwipes. The major fiber used innonwovensfor the disposable
is rayonwhilethe major fibersfor durables include rayon, polyster, olefinothers
used are nylon, vinyl, acrylic, cottonforcreating non woven’s a weboffibers is
first made. This means that fibers are laid by machines in random manner to
form this layer called web. Later these webs are laid over each other and are
then hold in place by
- Needle punching
- Bonding bymeans ofadhesive heat.
Needle punching is a mechanicalprocess which enlarges the fibers in the
web bypunchingthemwithneedles. Thisis the most inexpensive method such
non wovenare used infloorcovering in filters.
Bonding is a method where 2 or 3 more layers offiber webs are made to
stick to each other by adhesives. These are used in disposable items such as
protective gowns, hats etc.
Bonding bymeansofheat canbedone whenthe fibre webscontainat least
30% fibers. Since these synthetics soften by heat, heat is applied so that the
Commercial GarmentTechnology144
fibers bond with each others forming a non woven. These non woven provide
shape to cut parts ofgarments. So this webs can be used ad interlinings.
Felting
Woolis aprobablymost idealforfeltingbecausethefibersswellinmoisture,
interlock andremainin the conditionwhenpressed and shrunkwhen the fibers
have been selected and if necessaryblended with cotton or man made fibers
theyare caredinto a flat sheet or bat. Bats areplaced first one wayand thenthe
other layers untilthe desired thicknessisreached.Allowance has to be made for
shrinkage because steam and pressure of heavy pressures in the process of
felting mayincreasethe bats as muchas 20% thickness. To makethe felt fabric
stronger and morecompact the fabrics is placed inwarmsoapywater where it
is pounded and twisted. For heavy felt a weal acid is used instead of warm
soapywater.The clothis thenreadyfor finishing processconsistingofscouring,
dyeingpossiblypressingorshearingandtreatment withspecialfunctionalfinishes
to make it water repellent mothproofand shrinks create andfine resistant. Felt
is made for men and a women’s hat’s, women’s skirts, rests and slipper tables
covers. Paddlingandlining’s wovenfeltshavetheirplaceprimarilyintheindustrial
field.
Nets and braids
Net in geometrically shaped figured mesh fabric made of silk, cotton ,
nylon, polyester, rayonand other man made fiber. It comes indifferent sizes of
mesh and in various weights. On the other hand machine made net is closely
related to warp knitting because it is constructed on either a tricot or Rachel
warp knitting machine. The first nets to be made by machine were the warp
knitted tricot that appears about the middle ofthe 18th century.
Another type of net in the knotted square mesh type with knots with 4
corners to formthe mesh. Originallymade byhand and used byfisherman it is
now made by machine. These modernfish nets of linen cotton byman made
fibers are used for glass curtaining in contemporaryliving rooms, sun porches
and dens.
Braids
This is a method of interlacing 3 or more yarns or bias cut strips of cloth
over andunderone anotherto forma flat ortabularfabric. Thesebraidedtextiles
bands whicharerelativelynarrow can be used as belts, pullcards for lights and
for trimming for uniforms and dress tapes for pajamas’ and some shoe laces.
Severalwidth ofplastic and straw braidingcan be sewentogether to make hat
Paper - II Textile Science 145
shapes similarly by braids of fabrics or yarns may be sewn together to make
braided rugs.
Felt: Felt is the oldest knowntextile. Wooland related animalfibers such
as camel, goat, and hair haveunique feature ofenlargement when subjected to
heat, moistureand rubbing agitation. Thispropertyis the base offelt fabric.
lt ismade directlyfromfiberstreated inmachines designedto accomplish
thefeltingaction(heat, moisture andagitation).Despiteofwool, rayonorcotton
can also be used.
Felt does not fray or ravel. It can be blocked to shape in all directions
becauseit hasnogain. It hasgoodexcellent shockabsorbingandsoundabsorbing
tendencies. It haspoor drapabilityand lowtensile strength it cannot be tornbut
onlybe cut like woven fabrics it has no gain.
Lace fabrics: Lace isa fabric consisting ofdecorativedesigncreated with
thread s or yarns on a net like open background. They may be full of fabric
widthwhen used in making dresses or evening wear etc.
(a)Trimming laces:Awide varietyofpatterns available inlaces used for
trimming. Theyare produced having narrow width ranging from1cmor less
width. Theyare available at various costs and available at therange ofaverage
consumer.Theyareused asdecorative materials, apparels, householdmaterials.
(b) Nylon net laces: These laces generallycontain a net background on
whichpatternsaremade. Theyaremachine made, lessexpensiveandare mostly
used as curtains.
The elasticitypose difficultyincuttingand stitching. The patternshould be
properlyplaced over the fabric, taking care not to stretch the fabric and while
cutting also avoidsthe stretching offabrics.
As the lace fabrics are delicate they require gentle handling sewing and
care. Handsewing is most commonlyemployed as machinepuckerthe lace and
makesitunsightly. Handwashingismostlyrecommendedto preservethedelicacy
oflacefabric.Amild detergentshould be employed whilewashing these fabrics.
It isthemost complicatedofalltextilemakingprocesses.Theyareconsidered
as fabrics ofluxuryand delicacythough someare machine washable.
Theleavers’machineproducesthemostfinest andmost intricateofmachine
made laces. Theyare ofspecific style, type or range weight.
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Tuftedfabrics:Itisanothertypeofthepilefabricsnotproducedbyweaving
or knitting. Tufted fabrics are produced byneedling extra yarninto an already
wovenfabricofa relativelyopenweave construction.
Machinefortuftingare multi-needlemachinesandarecapable ofproducing
a tufted needle material. Theyare made onlyin relativelyheavyweight mostly
used for carpeting.
Conclusion
The appearance of a garment is greatlyinfluenced bythe fabric used for
construction not all the garments are suitable by some fabrics. To choose a
suitablefabricforaspecificendusecallsforbasicknowledgeinfabricconstruction
and types offabrics available inthe market.
Short Answer Type Questions
1. What is plain weave?
2. What are the types ofweaves?
3. What is knitting?
4. What are purlfabrics?
5. What is weft knitting?
6. What is warp knitting?
7. What are non woven fabrics?
8. What is jersey knit?
9. What are tufted fabrics?
Long Answer Type Questions
1. Write about classification ofknit fabrics?
2. How do you identifywarp knit fabrics?
3. Write about needle punched non woven?
4. Write about (a) felt fabrics
(b) Lace fabrics.
Paper - II Textile Science 147
I. Test yourunderstandings
State whether the following statements are true or false
1. Interlacing ofwarp and filling threads is called weaving. (T/f).
2. The simplest weave is a twillweave. (T/f).
3. The knit characteristics are bulky, looselyknitted, rib pearltricot. (T/f).
4.Anyfabric produced on a circular knitting machine is called a circular
knit. (T/f).
II. Test yourunderstandings
State whether the following statements are true or false
1. Nonwoven fabrics are made byweaving. (T/f).
2. Needlepunched nonwovens are made bythe methods that involves the
enlargement offabricsto hold themtogether.(t/f).
3. Thepressure ofair causesmechanicalbinding is spunlaced fabrics.(t/f).
4. Fusible nonwoven’s are made fromthermo plastic fibers.(t/f).
5. Felt fabricshave highdrapability.(t/f).
Answers forTest your understanding - I
1. True
2. False. (plain weaves).
3. True.
4. True.
Answers for test your understanding - II
1. False
2. True
3. False (frictionofwater jets)
4. True
5. False
Commercial GarmentTechnology148
Structure
7.0Introduction
7.1 Parts ofloom
7.2 Characteristics ofWoven fabrics
7.3 Weaves
Learning Objectives
After studyingthis unit, you willbe able to
• List out theparts ofthe loom
• Understand the various steps inweaving
• Know about variations ofthe plainweaves
• Types ofweaves
• understand the twillweave and satinweave
• List out the examples offabrics for the weaves
• Know about woven fabrics.
Looms
7UNIT
Paper - II Textile Science 149
Unit Preview
Thisunitgivestheinformationregardingtheweaving process, andthesteps
inweiving. i.e. different kinds ofweaves. It explains indetailabout plainweaves
and its variations, twillweave and its variation, satinweaveand its variations.
7.0 Introduction
The principles of weaving are known very clearlyperhaps a long ago as
400BC ourancestorsknewhow to make baskets and matsbyinterlacing twigs.,
reeds, and grasses. Later theylearnt how to twist together short fibers, suchas
wool and cotton, to form yarn and to weave the yarn in to cloth on a loom,
primitive looms were built around a convenient horizontaltree-branch, over
whichthe warpthreads were tied. The lower ends ofthethreads were fastened
to tietheminposition.
Woven fabrics aremade fromtwo ormore sets ofyarns interlacedat right
angles to each other the lengthwise yarns are called warp or ends and the
crosswise yarnsare called weft or filling or picks. Neat firmedges are formed
on bothsides along the lengthofthe fabric whenfilling yarn turns at the edges
during weaving. Theyare commonlyreferred to a “selvedges”.
Weaving is done ona machine called loom. The wayfilling yarninterlaces
withthewarpyarns produces designs inwovenfabrics. Weaving isthemode of
interlacement offillingwithwarp.
Allwoven fabricsare based onthree types ofweaves whichare termed as
basic weaves. The three basic weaves are plain, twilland satin. Most of the
other weave are variations or combinations ofthese three weaves.
7.1 Parts of the Loom
Fig. 7.1 Structure of the loom and its parts
1
4
5
2
3
67
11
15
8
12
16
9
13
10
14
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1. Warp yarn
2. Warp beam
3. Harness
4. Batten
5. Reed
6. Selvedge
7. Woven cloth
8. Cloth beam.
Warp Beam
Located at theback ofthe loomonwhichwith the warp yarns are wound.
It is acylinder on whichthewarp threads are inparallellines. Theyarns pass to
the front ofthe loomwhere theyare attached to cloth roll.
Harness
This is the frame consisting ofa number ofwires knownas heddles. Each
heddle consists an eye through which one or more warp yarns passes. The
harnessistheimportant partoftheloomasit hasupwardordownwardmovement
of warp yarn, ensures the correct running of the weft yarn over or below the
warp yarn to produce the designed pattern in the cloth. Harness contains a
number heddles.
Fig. 7.2 Harness
Heddle
It is awere witha holeinthe center throughthe warp yarngoes. There are
as manyheddlesas there are warpyarns inthe cloth. Allthe heddles are held in
two or more harnesses the warp is raised and lowered by a harness-haddle
arrangement. When the harness is raised shed is formed through which the
filling yarncanbe inserted.
9. Fell or edge ofthe cloth.
10. Shed.
11. Weft.
12. Shuttle.
13. Bobbin.
14. Dent.
15. Heddle.
16. Heddle eye.
Paper - II Textile Science 151
Fig. 7.3AHeedle
The Weaving Process
Thefirst stepinweaving is tostretchthewarporlongitudinalyarns. ,which
must be verystrong. The weft, woof or filling crosses the warp, binding the
warp threads at either side formtheselvage. The three essentialsteps after the
warp is stretched are shedding or raising every alternate warp yarn or set of
yarns to receivetheweft, picking orinserting the weft andbattening or pressing
home the weft to make the fabrics compact. In most primitive weaving these
operations were performed by the hands alone as in making rush mats and
baskets Gradually, frames for holding thewarp evenlystretched anddevices for
throwing the weft came into use.
Shuttle
This holdsthefillingortheweftyarnand ispassedbackwards and forwards
across loom.
Fig. 7.4AShuttle
Reed or Batten
It isa frame which is located directlyin front ofthe harness.
Fig. 7.5AReed
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This frame pushes forward each time the shuttle passes in between the
warp yarns and presses back the filling thread in position.
Cloth Beam
It islocated inthe front ofthe loomnearest to the weaver onthe which the
woven clothis wound.
Step in Weaving
1. Shedding : Raising one or more harness to separate the warp yarns
and formationa shed.
2. Picking : Passingthe shuttle through theshed to insert thefilling yarn.
3. Beatingup : Pushing thefillingyarninto placeintheclothwiththe reed.
4. Let off : Warp yarns are released fromthe warp beamso that weaving
maybe carried out.
5. Take up : Winding offinished cloth on the cloth beam
7.2 Characteristics of Woven Fabrics
Selvedges: In most of the materials the edges, which are known as
selvedges, aremade withheavierandmorecloselyplacedwarpyarns. Selvedges
is generally¼ to ¾ inches wide on fabrics.
The yarns are usuallythe same as those in the rest ofthe fabricexcept that
they are made firmer and stronger byincreasing the size or count of the way
yarns in selvedge. Fused selvedges are found on fabrics made from the heat
sensitive fibre. The applicationofheat melts and thenseals the fibre together at
the edges.
Count of the Cloth : Count is the technical term used to indicate the
number of warp and the weft (the filling yarn or picks) in one square inch of
fabric as it comes from the loom. If warps are 90 and the wefts are 80, the
count writtenas90 x80 anda fabric in whichthe warp yarns andweft yarns are
more in number it is called as high count fabric. Averylow count fabric is one
inwhichthewarp and the weft yarns number 28 and 24respectivelyexample in
surgicalgauze. The exact numberofwarp andtheweft yarns inasquare inchof
fabric canbe counted with the helpofan ordinarymagnifying glassheld over a
tightlystretched piece ofcloth. But allthis is not necessaryifthe aimis onlyto
judge whether the cloth is of a high or low count. If the weave is a veryclose
one and tiny spaces are visible between the weave and the cloth it could be a
closelywoven fabric.
Paper - II Textile Science 153
If the fabric is held against the light, the closeness of the weave or its
porositycan beeasilyobserved. Threadcount is an indicationofthe closeness
ofweaveandcanbeused bytheconsumerinjudgingquality, ravelling, durability
and potentialshrinkage. Fabrics with close weavegenerallyshrink less.
Balance of cloth
Low count fabrics are woven with a fewer interlacing per square inch to
make the fabric light-weight. Due to this a porous structure is formed. The
balance offabric is determined bythe proportion ofwarpyarnto weft yarns. If
the number of warp and weft yarns is nearly the same in a square inch the
fabrics havea good balance fora example, ginghamwitha count of96x88 and
guage withthe count of28x24 are materialwitha goodbalancebut the shirting
with 100 warps and 50 picks has a poor balance.Afabric with a poor balance
whenheldagainst thelight willshow moreyarnsrunninginonewaythatislength
wise only. Such a fabric is not good as it does not stand hard, wear and many
washings. Thestrengthofthefabriccanbetestedbytightlyholdingandstretching
a pieceoffabric, and rubbingit repeatedlyusing thumbs. Ifanyyarnslips out its
place and the tinyspaces betweenthe weave gets enlarged, it indicates that the
fabric is not as strong as it looks.
Yarns
Warp and filling have different characteristics and the fabric performs
differentlyinthewarpand filling direction. Stronger yarns are usedinthewarp-
wise directionas theyundergo moretension and friction thanweft yarns.
Most fabrics stretchedless inthe warpdirection. Warp yarnslie straight in
the fabric because ofloomtension. Theyshow less crimp. Warp yarns tend to
be stronger with higher twist. Decorative or specialfunction yarns, yarns with
slack twist, yarnswithlittle twist are usuallythe filling yarns.
Grain
The grain indicate the direction of the warp or weft yarns. Length wise
grainis apositionalongthe warpyarnsand paralleltoselvedges crosswise grain
is alongthe filling yarn.
Weaves
Weaves arenamedaccording to thesystemordesignfollowedininterlacing
warp and weft yarns. The basic weave used in fabric construction are: Plain
weave, Twillweave and Satin weave. These are the foundation weaves and
formthe basis ofallother types ofweaves.
Commercial GarmentTechnology154
Plain weave
Plainweave is the simplest ofallthe weaves.About seventypercent ofthe
woven fabrics available in the market today are woven in plain weave or it
variations. It is formed byinterlacing warp and fillingyarns ina patternofover
one and under one. (fig-1) In the first row the filling yarn moves over the first
warp yarnand under the second, over the third, under the fourth and so on. In
the second row, the filling yarn moves under the first warp yarn and over the
second warp yarn. These two rows are repeated to get the pattern of plain
weave.
Plain weave fabrics have no right or wrong side. Plainweave provides a
wide scope forintroducing variations inthefabrics byuse ofyarns ofdifferent
colours, different textured yarnandalso byuse ofthick and thinyarns. Fabrics
can be produced in large variety, withdifferent degrees of yarntwist and with
different degreesoftensions in the loom. Fabrics made bytightlytwisted warp
and loosely twisted weft make it easy for a napping finish to be given to it.
Example: flannelettes,stripedmaterial,plaidsaremadebyusingdifferent coloured
yarns at intervals eg. ginghams.
Plainweaveis made interesting byprinting and embossing. Plainweaving
also allows the use ofmanydifferent finishing processes to produce varieties
and different styles offabrics.
Plain weave is used in the construction ofthe fabrics fromalmost allthe
textile yarns cheapest to produce. It is the most serviceable ofall weaves as
fabrics,with this weave are easy to wash, dry clean, wear well and are
comparativelyinexpensive.
Fig. 7.6 Structure of Plain weave
Paper - II Textile Science 155
Plain weave fabrics
Cotton : Calico, cambric, canvas, cheese cloth, chintz, cotton, crepe,
flannelette, gingham, long cloth, muslin, organdy, seersucker and voile.
Linen : Cambric, dress linen, hand kerchieflinen and toweling
Wool : Crepe, Flannel
Silk : Chiffon, crepe de chine, crepe georgette, taffeta and voile.
Rayon : Chiffon, crepe, georgette, seersucker, organdy, taffeta and
voile.
Plain Weave Variation
Rib weave : It isthe variationoftheplain weave. Inthisheavier yarns are
used is the warp thanthoseis the weft andthis produces a ribbedeffect. Some
times the order is reversed and the heavier yarn is used in the weft. Eg. Faille
grass grain, broad cloth, poplinare someofthe examples.
Fig. 7.7 (a) RibWeave
(b)RibWeave
Commercial GarmentTechnology156
Basket Weaves
Basket weaves is a balanced weave. In this two or more yarns in both
warp and filling are treated as one and interlaced as in plainweave. The fabric
with basket weave have. Flenth and ifthe count is not very high the fabric is
evenporousand pliable. However, fabricswitharrangements such as3x3, 4x4,
6x6 snageasily. This weave isused inmaterialforsports coats and suits. This is
a comparitivelyloose weave and thereforethe fabrics are morelikelyto shrink.
Fig. 7.8 BasketWeave
Twill weave
This weave forms Wales diagonally across the face of the cloth. This is
brought about bythe interlacing ofwarpand filling yarns witha progression of
one at thepoint ofinterlacing
Paper - II Textile Science 157
Example : If the first filling covers warp yarns 2,3,4,5,6,8 and 9 goes
under 1,4,7, then the second filling will go over 1,3,4,6,7,9 and 10 and then
goes under 2,5,8, and so on. The simplest formofthe twillweaves is made by
throwingthe fillingyarnover a two warp yarns, thenunder one, over two under
one and so on. At least three harnesses should beused inthe loomto weave the
fabric. The direction ofdiagonalinthe weave can be created fromright upper
hand orleft upper hand called as right hand left hand twills respectively.
Avariationofthisweave is “Herringbone” structure. Inthisthe diagonal
directionis purposefullyreversed creating a designresemblingthe backbone of
fish. Thus it is termed as herringbone.
Another variation is made from a diamond pattern. Variations are also
introduced byusing yarns ofdifferent sizes, qualities and colours. Twillweave
has fewer point ofinterlacing than plainweave. So it permitscloser packing of
warp yarns to produce heavier fabrics whichresults in longer wear.
Twill weave produces strong material because ofthe tightlyyarns which
areused tobring out the diagonaleffect andthecompactnessofits construction.
Twill weave fabricsare mostlyexpensive becauseoftheirelaborate construction
on but theyare strong, standhard and long wear. This weave is generallyused
in wool and cotton fabrics where durabilityis a prime necessity. Twillweave
fabrics do not show dirt ordust as muchas the fabric woveninplain weaves do
and are therefore more suitable for dresses, men’s shirts and suits and children
garments.
The side onwhichdiagonaleffect ismore prominent is the right side ofthe
cloth. But when twill-weave fabrics are finished by“napping”the napped side
is theright side.
Fig. 7.9 Twill weave
Commercial GarmentTechnology158
TwillWeave On Fabrics
Cotton : Denimdrill, gabardine, jean, khaki, serge.
Linen : Table linen, towels, drills, and ticking
Wool : Broadcloth, cash mere flannelgabardine, tweed, serge, worsted
Silk : Twill, serge.
Satin Weave
Satin weave fabrics are characterized bylustre and smooth surface. They
are similar to twillfabrics except that the floats are long and diagonallines are
not visible.
Satin weave is one in which each warp yarn floats over four or more
number of filling yarns and go under one fifth yarn with a progression of
interlacement bymorethanone, thusavoidingtheformationofthe diagonallines
whichwillinterferewiththe lustre ofthe fabrics. Thelongerfloats permit closer
package ofyarns and thus satinfabrics normallycontainmore number ofyarns
than plainweave fabrics.
Satin fabrics have a right and wrong side. A high count of yarns in the
fabric provides strength, durability, bodyand firmness. Their smooth surface
provide more lustre. Low count fabrics are not durable and tendto ravelmore.
Fig. 7.10 Four float satin weave Fig. 7.11 Seven float satin weave
Sateen Weave
A variation ofsatin weave is sateenweave. It is characterised byhaving
filling yarn floats on the surface. These are less lustrous and less durable as
filling yarns are generallyweaker comparedto warp yarns.
Paper - II Textile Science 159
Fabrics inSatin weave: Washable satin, satin crepe, slipper satin etc.
Fig. 7.12 Sateen Weave
Suitability of Weaves Various End Uses
When suitabilityis a major factor, the consumer should carefullyconsider
the enduse or the purposefor which the fabricis to be used Plainweave fabrics
are firm and considered to be more serviceable as they are laundered or dry
cleaned, comfortable to wear and convenient. Theyare versatile, ranging from
light weight fabricsto heavyweight fabrics.
Light weight or sheer fabrics are suitable mainly for children’s dresses,
blouses, summer shirts, sarees and glass curtains, mediumweight fabrics are
mainlyused for shirt, women dresses, pyjamas and aprons. Heavyfabrics are
used forupholsterymaterials, suiting etc..Allplainweave fabricsare easilysew
able and areexcellent for creating styles throughmix and match.
Ribbed fabrics aresuitable mainlyfor furnishings andbasket weave fabrics
are suitable forshirting’s and furnishings.
Twill weave fabrics have interesting surface due to diagonallines on the
surface and are also durable. Theydo not show much soiland required only
little ironing. So theyare suitablefor work and sportsclothes.(Theyare mainly
used for menswear even in wool.).They keep up the shape well and so are
excellent for suitings.
Satin fabrics are not suitable for daily wear due to the presence oflong
floats. Theycanbe selectedfor occasionalevening wearforwomenappearance
and style governthe satin, hence theyare more expensive. Theyare considered
to be best lining fabrics for coatsand shirts because theyslide easilyover other
fabrics.
Commercial GarmentTechnology160
Conclusion
Abriefstudyofweavesenableagarment designertochoose suitablewoven
fabrics for different styles. Plain twill and satinare the weaver that form the
basis structure in allfabrics plainweave being simple and inexpensive forms a
good background for printing. Twillweave produces durable fabrics. Satin
weave produce smooth, lustrous fabrics that are suitable for linings
I. Test your Understanding
State whether the following statements areTRUE / FALSE
1. Twillweave forms waves diagonallyacross the faceofcloth (T/F)
2. Examples oftwillweave are Gabardine, Jean (T/F)
3. Satin fabric isnot lustrous and not insmooth surface (T/F)
4. Sateen weave have the filling yarnfloats onthe surface (T/F)
5. Sateen fabrics are suitable for dailywear (T/F)
Multiple Choice
Pick upthe correct answer fromthe following questions:
1. One ofthe steps in weaving are
a. shedding b. warp c. weft d. grain.
2. Edges are known as
a. count b. balance of cloth c. yarn d. selvedge
3. Basket weave is a
a. Balanced weave b. rib weave c. satin weave d. twill
weave.
4. Satin weave fabrics are characterized by
a. rough b. float c. yarn d. luster
5. Twillweave fabrics are mainlyused for
a. children’s wear b. ladies wear c. men’s wear d. instant
Paper - II Textile Science 161
Short Answer Type Questions
1. List out the basic weaves with2 examples each?
2. what are the variations ofplainweave?
3. which is the strongest ofallbasic weaves? Why?
4. List out the characteristics ofsatin fabrics?
5. write about basket weave?
Long Answer Type Questions
1. With neat labeled diagramdraw the parts ofloom?
2. what are the steps inweaving?
3. what are the characteristics ofwoven fabrics?
4. what is a weave? Describe plain weave with neat diagram?
5. Describe twillweaveand its variations?
6. Describe satinweave and its variations?
Answers or test your understanding - I
1. True
2. True
3. False- lusterand smooth surface
4. True
5. False- not suitable
Answers for Multiple choice questions
1. a. shedding
2. b. selvedge
3. a. balanced weave.
4. d. luster
5. c. men’s wear
Commercial GarmentTechnology162
Structure
8.0Introduction
8.1 Classificationsofstains
8.2 Generalrules to be observed inremovalofstains
8.3 Methods and reagents required for theremovalofstains
Learning Objectives
After studying this unit, the student willbe able to
• Explainthedefinitionofsatin.
• List out thevarious types ofstains
• Understand the generalrules to be observed inremovalofstains.
• Know about commonstains and the reagents required for removalof
stains onvarious fabrics.
Unit Preview
This unit helps inunderstanding thestains, the generalrulesto be followed
forremovingthestains, reagentswhicharerequiredtoremovestainsanddifferent
methods for removingthestains fromthefabrics.
Stains
8UNIT
Paper - II Textile Science 163
8.0 Introduction
Stain is spot or mark of discolorations on fabrics by the contact and
absorptionofforeignsubstances.
The need to clean and care for a household is always with us. For a
successfulstainremovalprompt action is important as a quick dealwith a stain
is more likelyto remove it simply.Withmost stains, trycoldwater first, flushing
the water throughthe materialifpossible. Make sure that thecleaners used are
known and awareness ofthere is also known. But as a generalrule, ifone can
safelyeat it.Forexamplelemonjuiceandbicarbonateofsodait isenvironmentally
kind as a cleaner.
Stainremovaland spotting is askillwhichcalls forexperienceanddemands
specialattention. The essentialfactors to be kept inmindwhile removing stains
are:
(1) The compositionand colour ofthe fabric.
(2) Thenature and age ofthe stain.
The stainremovalis amajorstore filled withdifferent formulae designed to
remove ourstains indailylife. It is agreatasset to thecleaningsolutions tackling
everything to wipe out dailystains. These stains with theirrespected removing
reagentsarespecifiedinthegivenchapter.Thusthestudentscanobtainmaximum
knowledge regarding the stains and their methods ofremovals.
8.1 Classification of Stains
Broadlyspeaking stains are divided into
(a)Animal
(b)Vegetable
(c) Greece
(d) Dye
(e) Mineral
Animal stains are those caused by blood, egg, milk, meat and juice. As
these containproteinmatter heat mustbe avoided inremovingthem. Otherwise
the proteinmatter gets fixed to the stain.
Vegetable stainsinclude those caused bytea, cocoa, coffee, fruit and wine.
These areacidic and therefore requirealkaline reagents to remove these stains.
Commercial GarmentTechnology164
Greese stainsmaybe just greese spots or some coloring matter fixed with
greese. Theseinclude butter curry, oilpaint, varnishand tarstains. Inremoving
these stains some greese or an absorbent is first used to dissolve or absorb
grease before the removal ofthe coloring matter. Asolvent soap is also very
effective for removing these stains fromwashable fabrics.
Dye satins maybe acidic and so that the nature ofthe stain is ascertained
before a specific removing reagent is used.
Mineralstains such as ironmould, black ink and certain medicine stains
are compoundsofa metalanddye. These are first treated byacid reagent to act
on the metaland thenbyanalkaline solutionto neutralize theacid reagent and
act onthe dye.
8.2 General rules to be observed in removal of the stains
1.Allthe stains are easilyremoved when fresh.
2. Ifthe nature ofthe stain is unknown it should be treated bythe least
harmfulmethodsfirst going one processto the next untilaneffective
agent is reached.
Theyareas follows:
(a) Soak in cold water.
(b) Soak in warm water
(c) Bleachinopen air, iftime permits.
(d)Treat withan alkaline solution
(e) Treat withanacid solution.
(f)Treat withoxidizing bleach.
If the above methods fail
(g)Treat withreducing bleach.
(h) Inthe event ofstainpersisting whichis unlikelytreatment with alkaline
solutionor with reducing bleachcan be repeated.
(i) Known stainsshould be treated withtheir specific reagents.
(j) Bleaching treatmentsshould be tried asthe last resort astheseshould be
takenfromseveralapplications ofweaksolutions rather thantheuse of
strongsolutioninone application.
Paper - II Textile Science 165
(k) Reagents maybe spread onto cotton and linenfabrics and boiling
water maybe poured throughthe fabric.
8.4 Common stains
(a) Ball pen
Reagents required: Methylated spirit
Method: Rub lightlywith methylated spirit, swabwith methylated spirit
using a padofblotting paper below. Same methodfor acotton,linen, silk, wool,
and synthetics fabrics.
(b) Boot polish
Reagents required : Methlated spirit
Method: Boot polishismade bydissolvingcertaincolors inwax. The wax
isremovedbymeans ofsolvents.Thiswillalso removethe color. Ifthecolor still
remains treatment withmethylated spiritwillcompletelyremovethe stain.
(c) Blood
Reagents required: Cold salt water, hydrogen peroxide.
Method: A fresh blood stain on clothing can be rinsed out in cold salt
water. Ifthe satin is dried bleach with a drop ofhydrogen peroxide.
(d) Gumand glue stains
Reagents required:Glycerinoraceticacidormethylated spirit orhot water.
Method:Treat withhot water tosoftenand dissolve thestain. The addition
of a few drops of glycerine will assist in dissolving the stains in some cases
otherwise few drops ofacetic acid also willhelp.
(e) Stained brass
Reagents required:Lemonsprinkled withsalt. olive oil.
Method : Agreener wayis to rubwitha piece oflemonsprinkled withsalt
or the other is rinses withdrythen rubs withthe olive oil.
(f) Greese or oil
Reagents required: Greese solvent, Frenchchalk or fullers earthpowder.
Method: Ifthe satin is fresh washwith hot water and soap and ifit is dry
treat withgreesesolvent and washwithhot water and soap forthe white cotton
and linen.
Commercial GarmentTechnology166
French and fullers earth are sprinkled on the stains to absorb the greese
then washit withwater.
Forunwashables
Treat withgreese absorbents spread Frenchchalk or alkalies earthon the
stainleave it for one hour brushoffthe powder.
Butter
Reagents required : Absorbent paper
Method : Scrape offas much as one can. Iron with warmiron between
layers ofabsorbent papers.
Lipstick
Reagents required: Bleaching powder, methylated spirit kerosene or
turpentine.
Method : Steep inmethlated spirit and washwithsolvent soap. Moisture
andsoftenbyworkingwithglycerine. Leaveit for short time andthenwashwith
soap or surf. For synthetics fabrics steep in kerosene or turpentine wash with
soap and hot water. Better trycold water first and thenwash in warmto soapy
hot water.
Candle wax
Reagents requires:Blottingpaper
Method : Put inplastic bag inthefreezer for sometime scrap it or sodified
it. Thenplacefabric betweensheets ofblotting paper and ironwitha warmiron.
Marking ink
Reagentsrequired:Iodinesolution, sodiumthiosulphate, salt. Tomato, sour
milk or curd, salt and lie juice.
Methods :Rubthestainwithcut tomatoand wash. Steepiniodine solution
andthenbysteeping insodiumthiosulphate solutionandwash.Bleachaccording
to the fabric. Rub salt and wash repeat tillstainis removed.
Mildew
Reagents required : Javelle water, potassiumpermanganate, oxalic acid.
Mildew is formed bythe growthoffungus on the damped fabrics
Method: (a)Bleachbysunlight
Paper - II Textile Science 167
(b) BleachbyJavelle water.
(c) Bleachbypotassiumpermanganate.
(d) Bleachwithhydrogenperoxide.
Potassium permanganate for cotton and linen: Dissolve one ounce of
permanganate crystals inone gallon ofwater.
Mildew onsilkand cotton:Takehalfofpermanganate crystalsinngallon
of water. Steep materials for 5 minutes till it becomes dark brown and then
remove the brownstainbyapplying anyone ofthe followingdilute solution of
sulphuric acidoroxalic acid oracidifiedhydrogenperoxide. Rinsethoroughlyin
three changes ofwater and washaccording to the typeofmaterial.
Mildewoncotton:Applysoaplather onthestains andcoveritwithFrench
chalk andplace it inthesunto bleach. Repeat the process tillthe satinis almost
removed thentreat iot with lime juice wash withjavelle water.
Preparation ofjavelle water or hydro chlorite. This can be prepared and
stored
Washing soda = 500grams
Boling water= 1 liter
Chloride oflime = 250 grams
Cold water = 2 liters.
Method: Make a solution ofwashingsoda and boiling watermixchloride
of lime with cold water stand the mixture for some time so as to settle down
decant a clearliquid and add it to washing soda solution. This willgive sodium
hydrochloride and calciumcarbonate willprecipitate.Allowthe precipitate to
settle andthenstainofftheclear liquid. This must be stored incoloredbottles as
it deterioratesinthe light.
Some procedurefor colored cotton, silk, wooland synthetic.
Jams and stains
Reagents required:Boraxsolution.
Method:Removejamstainsfromwashableclothesbysoakinginasolution
ofboraxand water then washas usual.
Tar
Reagents required: Oil, greese solvent, kerosene
Commercial GarmentTechnology168
Method : Spread a little on the stain, let it dry and repeat untilthe mark
disappears.
1. Ifnecessaryscrap first.
2. Rubwithoilor greaseusing a cleanclothand working fromedgeofthe
stain to the centre.
3. Treat withgrease solvent.
4. Treat with kerosene.
Chewinggum
Reagents required : Ice pack
Method : Put the garment in aplastic bag in thefreezer for a wholeor put
a icepack inthe gum. Crack offthe solidpieces. Sponge the remainderwithdry
cleaningfluid.
Iron stains
Reagents required:Toothpaste
Method : To cleanthe outside ofyours ironuse tooth paste as irontools.
Tea and coffee
Reagents required: Borax, washing soda, javelle water.
Method : For freshstain(cottonand linen):
Pour boilingwater throughthe stainfor drystain:
1. Steep inboilingwatercontainingsodaorboraxorbothorapplyglycerine
and steep inhot water soda solution.
2. Bleachwith javelle water.
3. Bleach withsodiumper borate.
For silkand wool fabrics
For stain: Steep in warmwater, repeat tillsatinis removed.
Dry stain
1.Applyglycerine and steep inwarmborax or weak ammonia solution.
2. Use hydrogen peroxide bleach.
3. Usehydrosulphite bleach.
Paper - II Textile Science 169
Chocolate
Reagents required :Boiling water, detergents.
Method : On clothing scrape off the solid chocolate with a blunt knife.
Pour boiling waterfroma height oruse detergent and work fromback ofstain.
Hair dye
Reagents required: Cold water, liquiddetergent ammonia.
Method : Rinse fabric immediately with cold water then wash in warm
water withliquiddetergent and ammonia.
Curry
Reagents required :Methylated spirit, diluted ammoniaor white spirit.
Method : Soak stain with methylated spirit, diluted ammonia or white
spirit
Ointment stain
Reagents required: Drycleaning solution, Liquid detergent.
Method :Trydrycleaning solution, thenrinse incold waterthen work in
liquid detergent and rinse again.
Pan
Reagentsrequired: Pottassiumpermanganate solution, sodiumper borate,
hydrogen peroxide.
Method: Treat withpotassiumpermanganate
Treat withsodiumperborate.
Treat withhydrogenperoxide and thenwashwith soap water.
Medicine
Reagents required :Oxalic acid, methylated alcohol.
Method: 1. Steep in warm water.
2. Steep in oxalic acid.
3. Steepin methylated alcoholorsurgicalspirit.
Egg
Reagents required : Soap and warmwater.
Commercial GarmentTechnology170
Method : Wash in cold water and then in warm water and soap. Apply
salt and pour warmwater.
Rust
Reagents required : Oxalic acid, dilute boraxsolution, salt and lemon.
Method :1. Steep in oxalic acid and thenrinse with dilute borax solution.
2. Steepinsolution ofsalt and lemon.
Scorch
Reagents required: Dryborax, Wet muslinammonia.
Method : Bleaching inthe sunlight is best.Applt soap lather to stain and
place it in the sun. Keep the stain with moisture and while it is inthe sun.
Rubwithdryboraxand wet muslin over stain.
Steep indilute ammonia place the stain inthe sunfor bleaching.
Nail polish
Reagents required:Acetme
Method : Applyto the stained area witha cotton woolpad this must not
be used onacetate rayon fabric.Ice cream:
Reagents required: Petrolor carbon tetrachloride, borax.
Method : (a) Wash in cold water and soap.
(b) Steep inwarmboraxsolution.
(c) Sponge withpetrolor carbontetrachloride.
Perfume
Reagents required: Ethylalchohol, Hydrogenperoxide.
Method: (a) Treat withethylalchohol.
(b) Bleachwith hydrogenperoxide.
Turmeric
Reagents required: Hydrogenperoxide, sun and grass.
Method : Soak inhot soap water and dry in sun or the grass.
Paper - II Textile Science 171
Apply a few drops of hydrogen peroxide leave for few minutes, rinse
thoroughlyand dryin the sun.
Conclusion
The processofremoving eachsatinwithreagents suitable to the fabrics is
important. Thereagentsshouldnot damagethe fabric. Hence correct procedure
should be followed to remove the satin from the fabric and at the same time
retainingftheoriginaltexture offabric.
Stain
1.Blood
2. Butter
3. Curry
Condition
Fresh
Dry
fresh
fresh
fresh
Freshdry
Synthetic fibre
Washincold water
Coverthesatinwith
French chalk place
the stained portion
between clean
blotting paper.
1. Wash with soap
and water.
2. Bleach with
sodiumperborate.
White cotton and
linen
Soak in cold water
and wash in dilute
ammonia.
Soak in cold water
and salt
Wash with warm
soapysolution
1. Wash with soap
and water.
2. Bleachinsunlight
and air.
3. Bleach with
javelle water.
Silk
Sponge with
cold water.
Same as white
cotton for
unwashable
fabrics apply
starch paste.
1.Same as
cotton use
French and
clean with
blotting paper.
Iron by hot
iron.
2. Cover by
solvent soap.
1. Treat with
solvent soap.
2. Treat with
p o t a s s iu m
permanganate
and ammonia.
Commercial GarmentTechnology172
4. Dye
5. Egg
6.Turmeric
(Haldi)
7. Ice
cream
8. Ink
Fresh
Fresh
dry
Fresh
Dry
Fresh
Fresh
Fresh
1. Steep in water
2. Wash with soap
and water.
3. Treat with
alcohol and dilute
acid or bleaching
powder.
1. Wash in cold
water and then in
warm water and
soap.
2. Apply soap and
thenwarmwater.
1. Same as curry
stain
1. Wash in cold
water and soap.
2. Steep in warm
borax
1. Apply salt and
lime juiceand leave
for some time
2. Soak in sour
milk and curd.
1. Wash with
water and soap.
2. Treat with
diluted bleaching
powder.
Same as cotton.
Steep in salt
solution.
Same as curry
stain
Same as cotton.
Same as silk or
wool.
1. Treat with
alcoholor
ammonia.
2. Bleach with
hydrogen
peroxide.
Same as
cotton
Steep in salt
solution
Same as curry
stain
1. Wash with
cold water
and soap.
2. Add
ammoniato
soap.
Treat with
sour milk or
curd for white
cotton
Paper - II Textile Science 173
9. Ball
point ink
10. Iron
rust
11. Lip
stick
12.
Medic-
ine
13.
Mildew
Fresh
freshand
dry
Fresh and
dry
Fresh and
dry
Fresh and
dry
Swab with
methylated spirit
usingblotting
paper.
1. Steep in oxalic
acid and then
rinse inborax
2. Steep in
solutionofsalts
and lemon.
1. Steep in
methylated
spirit washwith
solvent soap.
2. Use glycerine
and rinse
1. Steep in warm
water.
2. Steep in oxalic
acids and wash
withborax.
3. Steep in
methylatedalcohol
orsurgicalspirit.
1. Bleach with
javelle water.
2. Apply soap
lather and cover
with Frenchchalk
and place in sun to
bleach
Same as cotton
Same as cotton
Same as cotton.
Same as cotton
Bleachwith
hydrogenperoxide
Same as
cotton
Same as
cotton
Same as
cotton
Same as
cotton
Bleachwith
hydrogen
peroxide
Commercial GarmentTechnology174
14. Nail
and
varnish
15. Oil
and
paint
16.
Per-
fume
17.
Scorch
18. Shoe
polish
19. Tea
and
coffee
Dry
Dry
Fresh and
dry
Applyacetate to
stained area with a
cotton pad.
1. Steep in
turpentine wash
withsolvent soap.
2. Steep in alcohol
and theninsolvent
1. Treat with ethyl
alcohol.
2. Bleach with
hydrogenperoxide
1. Rubwith borax
andwet muslin
over the stain.
2. Steep in dilute
ammonia place the
staininsunfor
bleaching.
1. Scrape ofthe
stain ifdryapply
little grease wash
with soap and
water.
2. Steep in
turpentine wash
withsolvent.
(a) Pourboiling
water
1. Spread borax
and pourboiling
water.
2. Keep in glycerin
untilstainis
removed.
As cotton
For rayonalcohol
is not used.
Bleachwith
sodiumperborate.
Same as cotton.
Steep in kerosene
and turpentine and
washwithsolvent
Same as silk.
As cotton
Same as
cotton
Same as
cotton
Same as
cotton
Steep with
alcoholwash
withsolvent
Steep with
boraxsolution
Treat with
hydrogen
peroxide.
Paper - II Textile Science 175
Test your understandings
State whetherthe following statement istrue or false
1. Stainis a spot left on fabrics (t/f).
2. Stains are divided into 7 types (t/f).
3. Examples ofanimalstains are blood and egg (t/f).
4. Examples ofvegetables stains are milk and meat (t/f).
5.Allstain are easilyremovedwhen dry(t/f).
6. Ballpens can be removed bymethylated spirit (t/f).
7. Boot polishstain can be removed bywater (t/f).
8. Marking ink canbe removed byiodine solution (t/f).
9. Tar can be removed bygrease solvent (t/f).
10. Tea and coffee can be removed by borax (t/f).
Short Answer Type Questions
1. What is a stain?
2. What reagents are required for removing a) Ballpenb) Tar
3. How do you remove lipstick stainfromcottonfabrics?
4. Write thesteps involved inremovingthe mildew stains?
Long Answer Type Questions
1. What is a stain?Explainthe classification ofstains withexamples?
2. What are the generalrules to be observed inremovalofstains?
3. List out anyfour common stains andtheir removing agents?
Answers forTest yourunderstanding
1. True
2. False-5 types
3. True
4. False-coffee, tea, cocoa, etc
5. False- when fresh or wet
6. True’
7. False-methylated spirit
8. True
9. True
10. True
Commercial GarmentTechnology176
Structure
Finishes
9UNIT
9.0Introduction
9.1 Calandering
9.2 Singeing
9.3Tentering
9.4 Mercirizing
9.5 Bleaching
Learning Objectives
After studying this unit, the student willbe able to
• Explainthemeaning offinishes.
• Identifythe need whyfinishing process is required.
• List the variousfinishing process for fabrics.
• Understand the effect ofcalendaring infabrics.
• Understand theprocedure ofsingeing.
• Importance oftenteringis required for fabric.
• Reasonfor silkylustre and beautifulsheenis seen incotton fabrics.
• Importance ofbleaching and its use.
Paper - II Textile Science 177
• Distinguishingthebleachingagents.
Unit Preview
This unit helpsinunderstanding the different fabricfinishing process. The
finsihing processesincludes Calendring,, Signeing, Tentering, Mercerising and
Bleaching.
9.0 Introduction
Finish is defined as anything that is done to fibre, yarnor fabric to change
its appearance. The finish oftendetermines the fabric care required. Finishing
alters thesurface ofafabric and therefore itslookand feel. Ffabricsor garments
generallyhave to be finished to make the materialpresentable and attractive. It
is often the finish which increases the sales value ofthe textile goods finish is
usuallyapplied to fabrics.
As yarn and fabrics comes fromthe spinner weaver and knitter they are
often inunfinished condition. The materialmaybe harsh to handle and contain
impuritieseither thoseadded to facilitatethemanufacturingprocessorimpurities
which are naturalto fabrics. The materialmayalso be soiled andhave oilstains.
In fact, materialsfresh fromtheir manufacture are referred to as beingin a grey
orbrownstate. The finishingprocessesare requiredmake thematerialsattractive
theyalso improve their serviceability.
Classification of finishes
Finishes are classified on several basis the newly constructed fabrics as
theycome out of the loomare called greygoods. This does not mean that the
colors ofthe fabrics is grey, but it simplymeans that anyunfinished fabric must
pass throughvarious finishing process to make themsuitable for end use. The
aims ofthefinishing process are:
1. To makethe materialattractive.
2. To improvesuitabilityand utility.
3. To produce variety.
4. To give weight.
Finishes are classifiedin to two types
1. Mechanical
2. Chemical
Commercial GarmentTechnology178
Finishes
Mechanical Chemical
(use of mechanical methods) (use of chemical)
Finishes
Permanent Temporary Renewable
(Eg. Parchmentization) (Moire Calendering) (Stiffening)
Dyeing is sometimes considered part of the finishing process. It can be
sometimes be carried out at the same time that the fabric is straightened and
brought to its desired finish, width and length for other processes, the fabric
must be driedfirst and thenlightlydamped for the finalfinishing treatment. The
most commonfinishing process are listed below.The list is not a sequence nor
allare theprocesses used onallkinds offabrics. Some fabrics go through more
thanone process while each fabric is given its owncharacteristic finish.
9.1 Calendaring
Calendaring is essentiallyan ironic process. Most fabrics(and yarns too)
become stiffboard like when wet and dried under tension. Running the fabric
through a calendar removes the stiffness and makes it quite soft.At the same
time calendaringflattenstheyarns andmakesit so lustrous. The process consists
of applying a lot of pressure bypassing the cloth between cylinders ofheavy
weight of compressed cotton and steel. Rayon fabrics are not calendared as
heavilyascotton or linen, but silk oftenrequires fairlyheavycalendaring some
calendars use waxy calendars substances to give added luster in addition to
friction treatment bysteamheated pressure cylinders.
Calendaring flattens andclosethe threads ofthefabricto giveit therequired
smoothfeelandappearance. The finishdependschieflyonpressure, temperature
and moistures.
9.2 Singeing
The object ofsingeing is to remove the short fibers fromthe clothcoming
off a loom. The cloth is first passed over one or two stream heated copper
cylinders to remove moisture and to raise a nap. The projectingfibres are then
Paper - II Textile Science 179
singed(burnt) bypassing theclothoverahot plate orthrougha gas flameat high
speed, leaving thecloth with a smoothsurface. It is immediatelyput into water
to remove anysparks.
9.3 Tentering
To bring a fabric to the right width it is passed through a 20-90 feet long
tenteringmachine.Theclothiscarriedthroughthemachinebytwomovingchains
ofclips or pins one oneach side which grip the selvedge firmly.
Tentering is animportant and necessary operation because the fabric has
been pulled in length during bleaching, dyeing and drying and is therefore
generallynarrower thanthe required finished length. During the operation the
clip chaindivergefromthe entryend about one quarter or slightlyless thanthe
lengthofthe machine.As theclothis carried forward, grippedoneither sideit is
graduallywidened. In order that thestretching maytakes placeeasily, the cloth
is slightlydampened or steamed.After stretching it is passed througha hot air
chamber to dryand set at this width.
Fig. 9.1 Tentering or Straightening of the fabric
Commercial GarmentTechnology180
9.4 Mercerising
Applying the causticsoda under controlled conditionsgives cottonfabrics
a silky luster and beautiful sheen. It also gives the cloth a greater affinity for
coloring matters forespeciallydeeper, brighter shades with dye stuff.
The clothis impregnated withan18-20% solution ofcaustic soda for one
halfoftwo minutes at roomtemperatures. Theclothisstretchedwhilesaturated
andthenwashedoutwhileitisstillintension.Thetreatmentproducesapermanent
change inthe structure ofthecottonfiber.
Types of Calendaring
Variations ofcalendaring processinclude thefollowing moireed, embossed
and glazedfinishes. Theyare:
1. Moireing : One ofthe most interesting surfaces is the ‘moire’finish.A
cloth with a filling wiser rib weave is run between rollers engraved with many
lines and thusgivena watered effect. Onacetate clothes. The finishwillremain
ingoodconditionafterthefabricsarelaundered. Rayonsaregivenresintreatment
to set the design.
2. Embossing : The fabricis passed betweenheated rollersthat imprint or
emboss the design on the fabric. This design is less expensive than a woven
design.
3. Glazing :After the fabrics are bleached, dyed or printed theymay be
given a stiff polished or glazed surface. Starch glue or resin may be used to
stiffenthefabric. Thensmoothhot rollers that generatefrictionare applied since
the advent ofresins inthe finishingfield permanent finishgaze canbe applied to
chintz andother muslins.
Finishes that appealto touch: Some finishes improves the softness ofa
fabrics. For example softeners’ and hard builders must be used on nearly all
durable pressfabrics. Polyethylene emulsions improveabrasionresistance, sew
ability, fabrichand. These emulsions haveincreased inuse assofteners since the
advent ofdurable press. Other finishesgives weight and bodystillothers gives
crispness and stillothers warmth.
Napping : The warmth and softness of wool flannel or a brushed wool
sweater is due in part to the fuzzy soft surface called nap. It is the process of
raising short fibers ofcloth to thesurface bymeans ofrevolving cylinders with
metallic points. Cotton and synthetic fabrics of spun yarns maybe napped to
resemble woolin texture. Generally yarns used in the fabric should have low
twist.
Paper - II Textile Science 181
Parchmentizing : These are the permanent finishes on cotton and still
remain ofgreat importance. They were discovered by John Mercer in 1844.
Thehigherconcentrationofthesulphuricacidproducestheparchmentisingeffects.
Parchmentising acid probablygelatinizes the surface ofthe cotton and causes
the fibers ofcohere some extent.
Burnt out finish : Burnt out finishgives transparent effect possible on
blended fabrics onlylooks different fromothers. Formsopaque wovendesigns
against a transparent back ground..
Burnt out or etched finish : Etched effects are produced by printing
certainsolvents ona fabric make offibers ofdifferent fibergroups. For example
polyester, cottonor rayon. One fiberwillbe etched awayleaving it sheer as it in
itched rayon silk velvet. This results in producing opaques designs against
transparent backgrounds.
Thusstiffeningthefabric as distinct fromthe yarns whichare also stiffened.
Linen likeeffects are produced, but the acid is rinsedawaythe fabric isdried on
the stenter equippedwithjigging motionto breakdowntemporaryadhesions of
the warpand weft at points ofintersection. Organdie effects maybe produced
inthis way.
Alterationsoftheparchmentizing and mercerizing at low temperatures are
capable ofgivingspecialtransparent effects knownas swiss finish.
Starch less finish:To reducethe use ofstarchfor a crisp finishthat canbe
durable for repeatedwashings. Cottons are treated withresins. This starchless
finishispermanent and does not dissolves inlaundering.
Wash and wear: Permanent starch less finish can be used on curtains,
draperies, sheer cottonsfor apparel. It isused onorgandy, lawn, voile and other
sheet cottons.
Sizing, stiffing and starching: To increase the weight, bodycrispiness,
stiffness and luster cotton and polyester blends are stiffed. Generally starch,
glue, wax, casein, clayetc are used. It is not a permanent finish.
9.5 Bleaching
Bleaches areusedto rendercolouredordiscolouredfabricswhite. Bleaches
are used inlaundering to remove stainsthat do not respondto normalwashing.
Bleaches should not be used as cleansers. It is not possible to bleach dirty
laundry. Bleaching agents can be dividedinto two classes
1. Oxidizing bleach
Commercial GarmentTechnology182
2. Reducing bleach.
Oxidizingbleachsupplyoxygenthat combineswithstainsto formacolorless
compound. Normal as well as stained fabrics can be oxidized so the bleach
must be incontact with the fabric onlytillthe stain is removed. Longer contact
willweakenthe fibric.
Reducing bleachesworkbyremoving oxygenfromthecolouring matter of
the stain.
Conclusion
Finishing alters the surface ofa fabric and therefore its look and feel. The
finishing processes are required to make the materials attractive. They also
improvetheirserviceability.Finishingstraightensthefabricandbringsitto required
dimensions.
I. Test your understandings
State whether the statement is true or false
1. Calendaring is an ironing process. (T/F)
2. Singeingremoves the short fibers fromcloth. (T/F)
3. Tentering is not a finishingprocess. (T/F)
4. Caustic soda is used in mercerizingto give silkyluster to fabrics. (T/F)
5. 5-10% ofcaustic soda is used inmercerizing process. (T/F)
6. Bleaches are used in laundryto remove stains. (T/F)
7. Bleaching agents can be divided into 3 classes. (T/F)
8. Oxidizing bleachsupplies nitrogenthat combines’withstains to produce
colorless compound. (T/F)
Short Answer Type Questions
1. What is calendaring?
2. What are finishes?
3. What is singeing?
4. What is tentering?
5. What is mercerizing?
7. What are finishes?Write about calendaring and singeing?
Paper - II Textile Science 183
Long Answer Type Questions
1. What are the different typesofcalendaring finishes givento different
types oftextiles?
2. What finishappealto touch? Explain.
2. Differentiate betweennapping and parchmentization?
4. Howis burnt out finishdifferent fromparchmentisation?
Answers for Test yourunderstanding
1. True
2. True
3. False
4. True
5. False-18-20% is used
6. True
7. False- 2 classes
8. False - Oxygen
9. True
Commercial GarmentTechnology184
References
1. Textile fiber and their use - Hess
2. Fundamentals oftextiles and their care - Susheela Dautyagi
3. Household textiles and haundrywork - Deerga Deulkar
4. Modern textiles - DorothyLyle
5. The standard hand book ofTextiles -AJ Hall
6. Introduction toTextiles . E.E. Stout
7. Textile Fabrics and their selection
8. Clothing for moderns - Erwinand Kichener

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Classification of textile fiber

  • 1. Structure 1.0Introduction 1.1 Classificationoftextile fibres 1.2 Generalproperties oftextile fibres 1.3 Difference betweencellulose and synthetic fibres Learning Objectives After studyingthe chapter you willbe able to understand various terms associated with fibers. • Classifythetextile fibers. • List out various generalproperties oftextile fibres. • Distinguishbetween thevegetable and synthetic fiber. Unit Preview This unit gives the information regarding definition ofterms, staple and filament i.e. classificationoftextile fibresand generalproperties oftextile fibres. 1.0 Introduction Theword textileisderivedfromtheLatinterm“texture” forwovenfabrics. Thus by textiles we understand those objects which have been prepared by weaving. Textile have an important bearing on our daily lives and everyone Classification and general properties of textile fibres 1UNIT
  • 2. Commercial GarmentTechnology78 needs to know about textiles as we use them in some way or the other. To understand about textiles the study oftextiles willhelp to a great extent when we buytextile materials this knowledge willprevent us frommaking mistakes and we willbe able to purchase good qualitymaterials. There is a growing demand for textilesand clothing bypeopleofallwalks oflife. Yarns are produced bytwisting or spinningofthe textile fibres and in turn fabric is a structure produced byinterlacing or interloping ofthe yarns.. There are certain terms which are used very often in the studyoftextiles that are to be understood first. Most ofthe fabrics we use for various purposes are woven that means theyare constructed byinterlacing sets ofyarns that run along lengthwise and crosswise directions. Each yarn is made up of several fibres therefore it is essentialto know or to definethe terms like fibreyarns and fabrics. A “fibre “is defined as anyproduct capable of being woven or otherwise madeinto fabric.It issmallest visibleunit oftextileproduct.Afibrecanbedefined as a “pliable” hair like strand that is very small in diameter in relation to its length”. Fibresarethefundamentalunitsorthebuildingblocksusedinthemaking oftextile yarns and fabrics. Fibres arethefundamentalunitsusedinmaking oftextileyarnsand later on into fabric. Thus fibres are the essentialcomponents and basic units and are an essentialcomponents for making yarns. These fibres areofmanytypes. Definition ofYarns Fabricsmadeout ofdifferent fibresareavailableinthemarket. Thecommon fibres that are used for fabrics are obtained from different sources. There are few fibres which are naturally available. Still some fibres are synthetised by usingchemicalsand are knownassynthetic fibreseg. Nylonpolyster and acrylic fibres. Some fibresare manufactured byusing raw materialfromnatureand they are termed as man made fibres. Eg: Rayon, Polynosic, azlon etc. 1.1 Classification of textile fibres Let us see how fibres are classified According to the source from which textile fibres are obtained fibres are broadlyclassified into two ways.
  • 3. Paper - II Textile Science 79 Vegetable fibres or cellulosic fibres The fibres that are derived from plants are called vegetable fibres. The basic materialofallplant life iscellulose. Cellulose is made upofelements like carbon, hydrogen and oxygen. These cellulose fibres have certain common properties like low resilience, high density, and good conductor ofheat. They are highlyabsorbent and are resistant to high temperature. Cotton flax, jute, ramie are some ofthe examples ofvegetable fibres. Animal fibres The fibres which are obtained fromanimals are called animalfibres. Wool and silk are common examples ofanimalfibres. They are made up of protein molecules. The basic elements in the protein molecules are carbon, hydrogen, oxygen and nitrogen. Animal fibres have high resiliency but weak when wet because theyare bad conductors ofheat. Mineral fibres Theyare the inorganic materials shaped into fibres and aremainlyused in the fire prooffabrics.Asbestos is the example ofmineralfibre. Mineralfibres are fire proof, resistant to acids and are used forindustrialpurposes. Vegetable Eg. Cotton Linen Kapok Jute Hemp Animal Eg. Silk wool Mineral Eg. Asbestos Regenerated Cellulose Eg. Nitro cellulose rayon 2. Cupram- monium 3. Viscose Rayon Synthetics Eg. polyester, Nylon, Acrylic Acetate Cellu- lose Eg.Nylon Natural Manmade Fibres
  • 4. Commercial GarmentTechnology80 Man made fibres These refer to those fibres that are not naturallypresent innature and are made artificiallybyman. Manmadefibres have highstrength, strong when wet lowmoistureabsorptioncharacteristics. Examplesofmanmadefibresareviscose rayon, acetate rayon, nylon, polyester etc. Depending onraw materialchosen for making ofthe fibres theyareclassified as cellulosic fibres, proteinfibres and synthetic fibres. 1.2 General properties of textile fibres 1. Staple Fibres Natural or man made or short length fibres which measures in inches or fractionofinchexample 3/4 inch to 18 inchesexcept silk allother naturalfibres are staple fibres. Staple fibres are oflimited length. 2. Filament Long continuous fibres strands ofindefinite length measured in yards or meters fibres of continuous length long enough to be used in fabric as such Naturalsilkfilament is 360-1200 meters. Synthetic filaments canbemade many kilometers long. The onlynaturalfibre available is silk. 3. Texture It isthe tactile sensationexperienced when hand is passed over a surface. Staple fibres and fabrics made fromstaple are lightlyroughwhile filaments and fabrics made fromfilaments fibres are smooth.. 4. Resilience It means that when fibre is compressed and later when the pressure is released. It willtend to returnto its originalshape. Resistance to compression varies fromfibre to fibre. This qualitycauses the fabric to be wrinkle resistant with the resistance varying according to the degree of elasticity inherent in the fibre. Wool has outstanding resiliencywhile it is poorincotton. 5. Luster It isseenwhenlight reflected fromasurface. It is moresubdued thanshine. Silk andsynthetics have luster thancellulosic fibres. Infact syntheticshave high luster whichispurposefullyremoved during spinning.
  • 5. Paper - II Textile Science 81 6. Static Electricity It is generated bythe frictionofa fabric when it is rubbed against itselfor other objects. If the electricalcharge that is not conducted away, It tends to build up onthe surface and whenfabriccomesincontact witha good conductor a shock or transfer occurs. This transfer maysometimesproduce sparks. This is morefeelduring hot andhumid conditions. 7. Crimp Woolfibre ismore or less wavyand has twists. Thiswaviness is termed as crimp. Finerthewool morewillbethecrimpsinit. Marino woolwillhave30 crimps per inchwhile coarse woolhasonlyone or two. Thispropertyofhaving crimps gives elasticityto the fibre. 8. Elasticity It is the abilityofstretched material to return immediatelyto its original size. 1.3 Difference between cellulose and synthetic fibres Among natural fibres available cotton, wool and silk are the most commonlyused fibres for making fabrics.Among artificialfibres rayon, nylon and polyester are popular. The following are thedifferences betweenvegetable fibres andsynthetic fibres. Difference betweenvegetableand synthetic fibre S.No 1. 2. 3. 4. Cellulosic fibres Lowresiliency:Fabricwrinklesunless anyfinishingisgiven Highwaterabsorbency:Comfortable for summer wears, good for towel, hand kerchiefand diapers. Cellulosicfibresaregoodconductors of heat.eg: Cotton is a better conductor ofheat but less than that ofrayon. Identification: Cellulosefibres ignite quickly, burns freelywithsmoke and have an after glow and after burning Synthetic fibres High resiliency: Less wrinkles after washing and wearing Low moisture absorption: Easilywashable and easyspot removing. Synthetic fibres are also good conductors of heat they melt withhotorironictouchwithhot objects. Identification:Readilyburnsand melts giving a distinct plastic burningodour.
  • 6. Commercial GarmentTechnology82 Polyesterfibres burnreadilyandquicklywitha chemicalsmell. It continues to burn after removing fromflame and gives a plastic like in crushable bleed. Conclusion Fabrics are made out of different fibres are available in the market. The growth ofthe textile industryislargelythe work ofthe professionalpersonnel. New fibres new fabrics and new finishes make new demands for understanding the importance ofthe textile fabrics and their properties. Test your understanding-I State whether the following statements are true or false 1. Our primary needs are food, clothing and shelter (T / F) 2. Fibres are a pliable hair like structure (T / F) 3. Man made fibres are nylon and polyester (T / F) 4. Luster isthe naturaltendencyto returntheir originalcondition(T / F) 5. Static electricityis generated byfriction ofa fabric (T / F) forms and a greyfeatheryash. Cellulosic fibreshavehighaffinityfor dyes. Cellulosicfibres areresistant to moth but less susceptibleto mildew hence damp clothes should not be stored. Cellulosic fibres need ironing at low temperatures.Eg:wool Susceptible to strong mineral and organic acids stainsthat require acid treatment should berapidlyremoved. Synthetic fibres have low affinityfor dyes. Highly resistant to moths, mildew and insects. Synthetic fibresare adjusted withhighheatsettings.Hence it is good for embossed designing and easy for plant setting. Synthetic fibres get readily damaged due to acids.E.g.: Nylon 5. 6. 7. 8.
  • 7. Paper - II Textile Science 83 Test your understanding-2 State whetherthe following statements aretrue or false 1. Waviness is terms as crimp (T / F) 2. Examples ofnaturalfibres are polyester and nylon ( T / F) 3. Cottonis a cellulosic fibre (T / F) 4. Woolfabrics gives warmth (T / F) 5. Nylonis first synthetic fibre invented in 1930 (T / F) Short Answer Type Questions 1. What are fibres ? 2. What are the examples ofvegetable fibres ? 3. What are animalfibres ? 4. What are mineralfibres ? 5. What are man-made fibres ? 6. What is filament ? 7. What is staple fibre ? 8. What is Resiliency? 9. Define Luster and static electricity? 10. Define Crimp ? Long Answer Type Questions 1. Write the classification oftextile fibres ? 2. What are the generalproperties oftextile fibres ? 3. What arethe differences between cellulosic and synthetic fibres ? Answers to Test your understanding - I 1. True 2. True 3. True 4. False-resilience
  • 8. Commercial GarmentTechnology84 5. True. Answers to Test your understanding - II 1. True 2. False-synthetic fibres-polyster, nylon Naturalfibres-cotton,wool, silk 3. True 4. True 5. True
  • 9. Structure 2.0Introduction 2.1 Manufacture ofhand made cottonin India 2.2 Manufacture ofmachine made cotton 2.3 ByProducts ofcotton 2.4 Properties ofcellulose fibre - cotton 2.5 Fabrics ofCotton 2.6 Finishes for cotton 2.7 Consumer demand for cotton Learning Objectives After studying the chapter you willbe able to: • Understand the manufacturing ofcotton byhandand bymachine. • Identifythe structure and compositionoffibre. • Distinguish thevarious properties ofcottonthat is physical, thermal, chemicaland biologicalproperties. • Various characteristics ofcotton. • Understand about cotton fibre blends. Manufacture and Properties of Cellulose Fibres - Cotton 2UNIT
  • 10. Commercial GarmentTechnology86 • Know the consumer demand for cotton. • Understand the major end use of cotton. Unit Preview Thisunitdealswiththemanufacturingprocessofcottonbyhandandmachine made, byproducts ofcotton. Thevarious properties suchasphysical, chemical and biologicalproperteisofcotton, and variousfinishes for cotton. 2.0 Introduction Cotton is obtainedplant source and it is classified as a naturalmaterialas it is obtained from the seeds of cellulose seed fibre staple fibre measuring 10- 65mm in length and white to beige in color inits natural state. It is composed basically of a substance called cellulose. As cotton occupies 50% of the consumption offibres byweight inthe world it iscalled as the kingofallfibres. Cotton is the fabric for every home and is the most widely produced of textile fabrics today. It has now beenproved that India was thefirst countryto manufacture cotton.Among the recent findings at Mohenjo-Daro were a few scrapes ofcottonsticking to theside ofa sliversvase. Cottonis thewhite downy covering ofthe seed grown in the pods. The cotton plant grownin the tropics needs a climate with 6 months of summer weather to blossom and produce pods. Fig. 2.1 Cotton Boll
  • 11. Paper - II Textile Science 87 The cottonfibreis the shortest ofallthe textile fibres. Itslengthvaries from 8/10 ofaninchto 2 inches. Cottonwith short lengthfibresis technicallyknown as “short staple”. The onewiththe long fibresis called “long staple”and it more used since it is used for makingfine qualities ofcloth. Long staple is especially suitable asit is easyto spinand produces astrong smoothyarn. Itis also suitable for mercerizationa finishing process used to improvethe absorbency, strength and lusteroffibre. Cultivation of cotton Theprincipalcottonproducing regions are Egypt, southernUnited States, India, BrazilthewesternandsoutherncostofAmericaandEastIndies. It requires 200 daysto continue warmweatherwith adequate moisture andsunlight. Frost is harmfulto the plant. MarchandAprilmonths are suitable for plantation. Americaproducesmorethan40%oftheworld’scotton. Indiarankssecond to the United States as a producer and exporter ofcotton. 2.1 Manufacture of hand made cotton in India The tools and appliances used bycotton weaves consist ofa spinning wheel (charkha) and a spindle (takli). The cotton is the first ‘separated’ and ‘carded’. Abow shaped beater known as ‘dhun’is used for the purpose. The string ofthe bow is placed on the cotton and is made to vibrate bymeans ofa woodenhammer.These vibrations cleanses allforeignmatter such asseeds and leaves leavingsoft finecottonbehind. The fine cottonisrolled onstick to forma cylinder about halfa cubit (6 inches) long and halfan inch in diameter. This is tied to a spindle or takli. The charkha wheel is turned and the thin thread is gentlydrawnout untilit is about 300 yards longand rolled on acharkha which is wound on to a bamboo reel. The yarn is sent to weaving unit where it is woven into a cloth. After weaving the cloth is calendared witha blunt beater to giveit a gloss and to softenit. The cloth is then stamped, ticketed and made readyfor sale.
  • 12. Commercial GarmentTechnology88 2.2 Manufacture of Machine made cotton Preparation: Thefibres are first removedfromseeds inagin. Thisprocess is called ginning. Everybit ofthe cotton fibre is used in the manufacture . The fibre mass is then compressed into bales and shipped into spinning mills. The short ends left on the seeds after the longer fabric. Fibres have been removed are used in the production of rayon, plastics, dynamite and many otherbyproducts,whicharethenusedintheproductionofseedoil,hydrogenated fats, soaps and cosmetics. Forming the laps: Inthe step dirt fromcottonfibre is removed and fibres are made in to a soft rollor lap. Thenseverallaps are combined into one. Carding: These fibres are drawn together to form a loose rope called sliver. Doubling: Slivers arecombined here for uniformity. Combing: Thisprocessis continuationand refinement ofcarding process. Allcotton yarns for fabrics are carded but not allare combed. Yarns that are combed are finer evenand freefromallwoodystalkofthe plant. Theyare used for finer quality fabrics such as voile and organdie. Fabrics made from these fabrics are expensive too. The slivers are called carded slivers. Drawing: The slivers is then combined, smoothened and stretched. The sliversmaybe drawnreduced further insize andgivenaslight twistbyaprocess Cotton pods Ginning (RemovalofSeeds) Lap Formation Carding Doubling --> Combing Drawing Roving Spinning
  • 13. Paper - II Textile Science 89 called roving in which the slivers is passed through rollers and wound on to bobbins set into spindles. It is done ina speed frame. Roving: Thebobbins areplaced ontherovingframewherefurtherdrawing and twisting takesplace untilthe cottonstock is about a pencillead in diameter. Spinning: Doneonthe spinning framewhere the stockpassesthroughsets ofhighspeed rollers and gives the yarnofdesired thickness. Weaving and dying:The yarn is then knitted or woven in anyone ofthe varietyofweaves and structures. Warp yarns are usuallymorestronglytwisted thanfillingyarnssincetheymustwithstandgreaterstraininweavingandfinishing. Dye stuffs maybe applied to raw cotton, yarn or piece goods. Finishing:Itincludesstarching,calendaring,sanforizing,mercerizing orother finishes as it is necessaryfor the particulars use for which theclothis intended. These finishes may be applied to yarns but are usually applied to fabric. The fabrics maybe given these specialfinishes before or after dyeing. 2.3 By products of cotton Cotton linters: Linters are short, fuzzy fibres that remain on the seeds after theyhave beenseparated fromthe fibre inthe cotton gin. Theyareused in the manufacturing ofrayonand acetates, plasticsand photographic film. Fig. 2.2 Cross Section Fig. 2.3 Cotton Fibre under the microscope Hulls: These are outside portion ofthe cotton seeds rich in nitrogen and used as fertilizers, paper cattle feed.
  • 14. Commercial GarmentTechnology90 Inner seed: It yields cotton seed oilwhichis used as cooking oils and in the manufacturingofsoap. 2.4 Properties of cellulose fibre- cotton 1. Physical properties a. Structure:Thecottonfibreisshort (1/2inch-2 longinch)andcylindrical ortubularasit grows. Thecottonfibreisessentiallycelluloseconsistingofcarbon, hydrogen and oxygen. Bleached cotton is almost pure cellulose raw cotton contains about 5% ofimpurities. b. Strength: Cottonfibre is relativelystrong which is due to the intricate structure and70% crystalline. c. Elasticity: Cottonisrelativelyinelasticbecauseofits crystallinepolymer systemand for this reason cottontextile wrinkle and crease readily. d. Hygroscopic moisture: Cottondoesnot hold moisture so wellas wool or silk but absorbs it and so feels damp much more quickly. It also rapidly spreadsthroughout the material. e. Electricalproperty: Thehygroscopic nature ordinarily prevents cotton textile materials fromdeveloping static electricity. f.Absorbency:As cotton has cellulose it is a good absorbent offibre. 2. Thermal properties Cotton fibres have the ability to conduct heat energy, minimizing any destructive heat accumulationthus theycanwithstandhot ironing temperature. Drap ability: Cotton does not have good body to drape well in shape. The type ofconstructionofthe fabric mayimprove this property. Resilience: Cotton wrinkles easilysome wrinkle resistant finishes may reduce this property. Cleanliness and wash ability: Though cotton absorbs dust due to its rough nature. It canbe washed easilyin the hot water andstrong soaps without damaging the fibre. Lustre:Thenaturalcottonhas no pronouncedlustre. This canbeimproved bythe mercerizationfinishofthe cotton(that issodiumhydroxide treatment). Shrinkage: Thefibre itselfdoes not shrink but cottonfibrewhichhas been stretched in the finishing process tends to relaxback creating shrinkage.
  • 15. Paper - II Textile Science 91 Heat conductivity: Cotton is the better conductor ofheat than woolor silk but not as good as rayon. 3. Chemical properties Action of acids and alkalies Strong acids willdestroythe fibres immediately. Diluteinorganic acids will weakenthe fibre and ifleft drywillrot it. Therefore after treatment withacidic solutions cottonarticles should be thoroughlyrinsed inwater. Theyare affected verylittle byorganic acids. Theyarealso quite resistant to alkalisevento strong caustic alkalies at hightemperature and pressure. In 8% NaOH cotton fibres swells, spirals, twisted uncoiland shrinks and become thicker. The resultant fibre issmoother, lustrous, and strongerand has increased water and dye absorption. Effect of bleaching: These have no effects until used in uncontrolled conditions andwith heat. Effect of sunlight and weather: Ultraviolet rays of sunlight affect the strength offibre and change the colour to yellow whenexposed to prolonged period. Pollution also effect fibre.Concentrated and diluted mineralacids like sulphuric acids willdiscolour fibre . Affinity to dyes: Cottontakes in dyes better than linen but not as readily as silk and wool. If a mordant is used cotton is easy enough to dye mordant colours, direct or substantive dyes should be applied to the cotton. Effect of perspiration: Both acidic and alkaline perspiration discolours the fibre. 4. Biological properties Resistancetomicroorganisms:Themildewandbacteriadamagescotton. Resistance to insects: Moths and beetles willnot affect or damage the cotton. But the sliver fish eatsthe cotton cellulose. 2.5 Fabrics in cotton Flannelette and flannel:Asoft napped cotton fabric its warmth in wear is due to the fact that the nap traps a layer ofair between the bodyand the cold outside. Incompositionit isthesameasordinarycotton,buttreatment inweaving makes it veryinflammable. For this reasonattempts have beenmadeto make it fireproof bysaturating the fibre with metallic salt, but ingeneralfire proofing does not withstand washing.
  • 16. Commercial GarmentTechnology92 Organdie: Athin light fabric in plain weave with a verystiff finish. It is madefromgoodqualitycombedyarn. Theyarnis made fromlongstaple cotton and is spunis withmanytwists. This along withthefinishing process produces its characteristic transparent crispness. The aimis to give a permanent finish. The fabric is used for summer and evening wear. Muslin: This is a cool, very light, and plain weave cloth also used for summer wear. The name derives fromthe city ofMosulwhere the fabric was first made muslins wear not always plain, silk and even gold stripes woven in whenmade inmosul but as cottonwas grownmore plentifullyand the women could spinyarns ofgreat fineness, cotton yarns graduallysuper seeded silk. 2.6 Finishes for cotton The resinandthenonresinfinishesgivethecottonsomeeasyand minimum care features of as synthetics.Advances in antibacterial mildew resistant and flame resistant treatmentshave improved the effectivenessofthe performances ofcotton invarious end uses. Regular finishes like singeing for smoothness mercerization for strength, lurtre andaffinityfor dyes, sizing and calendaring for lustre, maximumstiffness bodyand smoothness.Specialfinishlike sanforizing formaximumpre shinking, crease resistant, antibacterialfinishes, mildew and rot treatment napping for softness, warmth, absorbencyand mothrepellent treatment are common. Fibre blends Amongthevarioustypesofblendsavailableinmarkettodaypolyster, cotton terycotton, silk, linencotton, viscose rayonandcotton and nylon. Reasons of blending are: To facilitate processing. -To improve properties like dimensionalstability. - To produce better performance. - To improve textute, hand or feelappearanceoffabrics. - To produce multicolor fabrics. - To reduce cost. 2.7 Consumer demand for cotton Versatality: Cottoncanserve for food (cottonseedproducts) forclothing and for shelter. Cotton fibre canbe spun alone or it can be blended with other
  • 17. Paper - II Textile Science 93 textile fibres such as linen, wool, silk, viscose rayon, polyster, nylon. It serves the purpose of clothing or apparel, home furnishing and industrialfabrics by giving comfort, durability, fashion and easefor care etc. Durability: Due to naturaltwist cottonspinsso wellthat it canbe twisted verytightly. Hence tightlytwisted yarnsproduce durable fabrics. Comfort: Cottonconducts heat awayfromthe bodyand allowsthe cooler temperature outside to reach the body, so it is a cool materialfor summer or tropicalwear. Knitted cotton is used as comfortable wear. Fashion rightness:Fashiondesigners ofvarious countrieshaveconsidered cottonglamorousenoughto include intheir collections. Ease ofcare: The factors oflight, laundering, ironingand perspirationare commonconsideration incolor fastness to cotton. Economy or price: Cotton materials are flexible to fit into all types of economic group. Byproducts ofcottonare used for manypurposes. Major end uses Cotton is used forhome furnishing : Towels are most common as it is highinabsorbency, wide range ofcolors, washabilityand durability. Sheets and pillow cases aremostlyblends ofcottonwithpolyester or made ofpure cotton. Drapes, curtains and upholsteryfabrics are made ofcotton and its blends. Since cotton can be autoclaved at high temperatures, absorbency, washability and low static build up are important factors for use of cotton in hospitals. Industrialuses includebook bindings, luggages, and handbags, shoes and, slippers, tobacco cloth, woven wiping cloths as andwallcovering fabrics. Wide range ofwearing apparels: blouses, shirts, dresses, childrenwear, active wear, separatesswimwear, suits, jackets, skirts, pants, sweaters, hosiery, bedspreads, comforters, throws,sheets, towels, tablecloths,tablemats, napkins. Consumer Demand for Cotton Versatality Economy Durability Comfort Fashion Ease of Care
  • 18. Commercial GarmentTechnology94 Conclusion Cotton continues to be the world’s major textile fibre despite of many synthetics. It is the oldest and most versatile ofall fibres with good properties when blended withother fabrics. The mainreason for use ofcottonis its good weaving qualities, low cost, high absorption, excellent, abrasion, stability to repeatedblending. Itcanbesafelyironedevenat hightemperatureof425degrees F. It has excellent wash and wear and wrinkle resistance and also good ifresin treated. I. Test your understandings State whether the following statement are true or false 1. Cotton does not have color retention property. ( T / F ) 2. Cottoncannot be blended withother fibres. ( T / F ) 3. Cotton conducts heat awayfromthe body. ( T / F ) 4. Cottonis used for home furnishings. ( T / F ) 5. Cottonis moth repellent and provides softness and warmth. ( T / F ) II. Test your understanding State whether the statements are true or false 1. Cotton is naturalfibre. ( T / F ) 2.The cottonwith short length fibre is called as short staple. ( T / F ) 3. Hulls are inside portion ofcotton seeds. ( T / F ) 4. Cotton is not good absorbent. ( T / F ) 5. Cotton is a good conductor ofheat. ( T / F ) Short Answer Type Questions 1. What is staple? 2. Give the steps for recent advances in handmade sector? 3. What are the by products ofcotton? 4. What are physicalproperties ofcotton? 5. What are the uses ofcotton? 6. What are the reasons for fibre blends in cotton?
  • 19. Paper - II Textile Science 95 Long Answer Type Questions 1. What are the chemicalproperties ofcotton? 2. What are the steps involved inpreparation ofmachine made cotton? 3. Write short notes onfollowing (a) Kapok (b) Flannelette and flannel(c) Organdie 4. What are the characteristics ofcotton? 6. Write the consumer demand for cotton? Answers for text yourunderstandings - I 1. False 2. False 3. True 4. True 5. True. Answers for text your understandings - II 1. True 2. True 3. False-outside 4. False-due to cellulose fibre it is good absorbent. 5. True.
  • 20. Commercial GarmentTechnology96 Structure 3.0Introduction 3.1 Historyofsilk 3.2 Productionof silk 3.3 Historyofwool 3.4 Manufacturingofwool Learning Objectives After studyingthis unit, you willbe able to • Understand the varioustypes ofsilk. • Explainthemanufacture ofsilk • Describe the physicaland chemicalproperties ofsilk • Explaintheclassificationofwool • Understand manufacturingprocess ofwool. • Explain the physicaland chemicalpropertiesofwool. Unit Preview Thisunitgivesustheinformationregardingthe manufactureofphysicaland chemicalproperties ofprotein fibres. Manufacture and Properties of Protein Fibres 3UNIT
  • 21. Paper - II Textile Science 97 (1) Silk (2) Wool 3.0 Introduction Silkisconsideredas“Queenofalltextilefibres”asit hasbeautyandelegance and good properties ofperformance. Silk is the naturalproteinfiber obtained from silk worm cocoons. Japan is known for producing best variety of silk. India produces different varieties of silk and is famous for hand woven silk textiles. There is a tremendous silk production increase in recent years. The production ofsilk is called Sericulture. To obtain qualityand quantity ofsilk rearing conditionsare controlled carefullythroughoutthe life cycleofsilkmoth. These are two types of silk mulberry or cultivated silk and wild silk. Cultivated silk iscreamysilk white oryellowishwhite in color. White wild silk color rangefrombrownish to goldenyellow incolor. 3.1 History of silk Sericulture or silk production has a long and colorfulhistoryunknown to most people. For centuries the west knewverylittle about silkand people who made it pliny, the romanhistorianwrote inhis naturalhistoryin70 BC“silk was obtained byremoving the down fromleaves withthe help ofwater”. For more than 2000 years these Chinese kept the secret ofsilkaltogether to themselves. According to legend the beginning ofhistoryofuse ofsilk as textile fibre goes back to 260 BC. When fourteen year old wife ofChinese emperor Huang-Ti discoveredthe secret ofdrawingthe filament fromcocoonofthe silk wormand producingafabricfromthe filament.This youngprincess Si-ling-chiis knownas ‘godess ofsilk worms’and isthe centre ofreligiousceremonies connected with the care ofsilk worms and the production ofsilk has long been an important factor ineconomyofempire. Silk has never lost its luxuryfieldappealand todayis shownbyallhouses in their top fashion products some designers are working only on silk. It is everywhere in fashionpicture. In intimate wearand outer wear, hand bags and shoes. 3.2 Production of Silk Silk worms feed on mulberry tree leaves and therefore for rearing them, the growingofmulberry treesis the first essentialstep. These are grownbythe agriculturists. Silk worms havea short life ofonlyabout two monthsand during which these pass through the following four stages1. Egg 2.wormor larvae 3. Pupa and 4. moths.
  • 22. Commercial GarmentTechnology98 Silk worms are made to lay eggs on specially prepared paper for this purpose. Theeggscanbestored incoldstorageforsixweeks. Eggs arecollected and kept at low temperature untiltheyare hatched. Eggs take tendays to hatch Emerged caterpillars ofant head size are fed on fresh mulberryleaves.At this stage the wormneeds specialcarebamboo trays with straw mats are provided for them. Whenthe caterpillar is about eight weeks old it secretesaviscousfluid fromtwo glandsonits head whichoozes out fromthe commonopening near its mouth. The fluid is called ‘fibrion’.At the same time it also secretes a gummy kind offluid called ‘sericin’whichpasses throughthe sameopening. The fibroin gets hardened whenexposed to air. Thesilk wormspins around itselfto forma cocoon. Thecocooncontains 2000 to 4000yards ofreelablesilk. Forseparating thesilkthreadfromthe cocoons theyareimmersed inhot water.Thisimmersion also kills the warminside. Thenthe cocoons are dries and stored. Fig. 3.1Silk moth and eggs Fig. 3.2Larva ofItalianBombyx mori silkworm moth Fig. 3.3 Cocoon of Bombyxmori Fig. 3.4 Male Bombyxmori or mul- berry-feeding silk wormmoth
  • 23. Paper - II Textile Science 99 Reeling: Theprocess ofunwinding the filament fromthe cocoonis called reeling. The care and skillin the reeling operation prevents defects in the raw silk.Asthe filament ofsingle cocoonis too finefor commercialuse, threeto ten strands are usuallyreeled at a timeto produce the desired diameter ofraw silk thread. Several cocoons are placed in hot water to soften the gum and the surfacesarebrushedlightlytofindtheendsthefilaments. Theseendsarecollected, threaded througha guide and wound on to a wheelcalled ‘reel’. Throwing:As thefibres are combined and pulled onto thereel, twist can be inserted to hold the filaments together. This is called as throwing and the resultingyarnis‘thrownyarn’. Thisyarnlatergoestoweavingorknittingindustry based the type of yarn produced. Spinning: Short ends ofsilk fibres fromthe outer and inner edges ofthe cocoons and frombroken cocoons and spuninto yarns in a manner similar to that usedfor cotton. This is called spun silk. Degumming: Sericinor gumup to 30% ofthe weight ofthe silk fibre. It is not usuallyremoveduntilafter the clothis wovenbecause servesas warp sizing that protects theyarns frommechanicalinjuryduringweaving. Sericinremains onthefibreduringreeling and throwingbeforefinishing, the gumis removed by boiling the fabric in soap and water. The presence ofgumand sericinincreases the tendencyfor the silk to water spots on fabrics when ironed. Bleaching: Silkthread is treated with hydrogen peroxide. Dyeing: Silk has great affinity for the dyes. Acid dyes produce brilliant shades on silk. Printing: Silk maybe left plainormaybeprinted byanymethodlike roller printing, Screenprintingorblockprinting.Silksareusuallydriedandthenprinted. Finishing: Silk fabricsrequire veryfew finishes becausetheyhave natural lustre, softnessand drapability. Weighting of silk: When silk is boiled to remove the excess of natural gumorsericinit loosesweight. Thislossofweight isreplacedthroughtreatment bymetals liketin, aluminiumetc inwater solutions. These arenot removed by washing. Weighted silk isnot durable because sunlight and perspirationweakens fibres. Heavyweighting causes silk to crack.
  • 24. Commercial GarmentTechnology100 3.2.1 Various types of silk Wild silk: Silkproduced bymoths ofspecies other than bombyxmori. It is brown incolor more uneven and coarser. It is usuallycalled Tussar silk. Waste silk orsilk noil: Short ends ofspunyarns or inblends with cotton or wool. Sometimes it is called waste silk. Dupion: Silk yarns made fromtwo cocoons that have beenformed in an interlockedmanner.Theyarnisuneven,irregularandlargethanregularfilaments. It isused inmaking shantungand duppioni. Raw silk: Silk that has not had anydegumming. Spun silk:Yarns made fromshort fibres frompierced cocoons and short ends and outside and inside the edges ofcocoons. 3.2.2 Properties of silk Microscopic structure Silkhas itsuniqueproperties. It issoft, supple, strong lighterinweight than anyothernaturalfibre. Silk is priced for itsweight. Silk is anaturalproteinfibre where the protein fibroin is held bya gummysubstance . Fig. 3.5 Microscopic structure of silk Microscopic properties Strength: Silk is the strongest naturalfibre. It has a tenacityof2.4 to 5.1 grams per denier. More over smoothness ofthe silk filament yarn reduces the problemofwearfromabrasion. The strengthofthe spun silk yarns depends on the lengthofsilk staple.
  • 25. Paper - II Textile Science 101 Shape and appearance: Silk filaments are very fine and long. They frequentlymeasure about 1000 to 1300 yards inlength. The widthofthe silk is from9 to 11 microns. Elasticity: It is an elastic fibre and its elasticityvaries as it is naturalfibre. Silk fibre maybe stretched from1/7 to 1/5 its originallength before breaking. Cultivated degummed silk viewed longitudinally under a microscopic, resembles a smooth transparent rod under microscope. Silk in the gum has rough irregular surface. Wild silk tend to be quite uneven and is some what dark. It mayhave longitudinalstriations. Resilience: Silkretains the shape and resists wrinkling rather well. This is more in fabrics made frompure silk rather than spunsilk or weighted silk. Drapabilty: Silk has a pliabilityandsuppleness’ that aided byits elasticity and resilience givesit excellent drapability. Heat conductivity: Since silk is a proteinfibre. It is a non conductor of heat like wool. Hence it is used for winter apparel. Absorbency:The good absorbtive propertyofsilk also contributes to its effect inwarmer atmosphere. Silk generallyabsorbs about 11% ofits weight in moisture whichmakes silk for easydying and printing. Cleanliness andwashability: Silkis hygienicmaterialbecauseitssmooth surface does not attract dirt. It canalso be easilycleaned bymild soapsand dry cleaning. Shrinkage: Dueto the filament inlength, smoothsurfacesilkhave normal shrinkage which can be easilyrestored by ironing at moderate heat and damp conditions. Effect oflight: Continous exposureto light weakens silkfaster thaneither cottonor wool. Chemical properties Resistance to mildew: Silk willnot be affected bymildew unless left for time in damp state or under extreme conditions oftropicaldampness. Reaction to alkalis: Silk is not as sensitive as wool to alkalis. It maybe affected inconcentrationsand hightemperatures. Coldconcentrated solutions ofalkalisuchas soda or causticpotashhas slight actiononsilk. Heated solution dissolved silk.
  • 26. Commercial GarmentTechnology102 Reaction to acids: Concentratedmineralacids dissolve fasterthanwool. Organicacidsdo not harmthemwhilemediumconcentrated HCL willdissolve silk. Affinityfordyes: Silkhasverygoodaffinityforaciddyes butlight fastness isunsatisfactory. Resistance to perspiration: Silk fabrics are damaged by perspiration. The silk itselfgets deteriorated in the presence ofperspiration. Reaction to bleach: Strong bleaches contain sodium hypochlorite will deteriorate silk. Mild bleaches like sodium perborate and hydrogen peroxide maybe used with normalcaution. 3.2.2 Uses of silk Silk isanexpensive luxuryfabricusedformakingdifferent garments. Silkis used primarilyin apparelandhome furnishing items becauseofits appearance and cost. Silk is extremely versatile and can be used to create a variety of fabrics fromsheer chiffons to heavybeautifulbrocades and velvets. Because of silk absorbency it is appropriate for warm weather wear. Because of its low conductivityit isusedforcoldweatherwear,also infurnishingsilkisoftenblended with otherfibres to add soft luster for furnishing fabric. Occasionallyexpensive hands made rugs are made fromsilk. 3.3 History of Wool Woolhas the one ofthe first fibres to be converted into fabric. Woolfibre grows from skin of sheep. It is composed of protein known as keratin. It is crimp and has scales on its surface depending upon the breed of sheep. The naturalproteinfibre consist ofamino acids. Woolhas 19 amino acids, keratin, proteinandother organic acids. Man uses woolas clothing in the veryearlystages ofhuman history. The primitivemanisused it intheformofskinofcertainanimals to protectas wellas to decorate his body. Man then discovered the use of hair of sheep after interlocking and twisting themtogether under pressure and thus hair ofsheep were used in making fabrics The interlocking of woolen fabrics is known as felting. Wool was probablyknown to the primitive man as he used sheep skin to cover his bodyeven before the discoveryofother fibres.
  • 27. Paper - II Textile Science 103 Woolis yellowishwhite fibre and has mediumluster. It isconsidered to be weak fibre than manyother fibres however other properties suchas resiliency and elasticitycompensatefor low strength. 3.3.1 Structure of wool When the wool is fibre is untwisted it shows a kinky appearance. The length varies from 1,1/2 to 18 inches, the long fibres are coarser than short fibres. Fig. 3.6 Microscopic structure ofWool When observed under microscope the surface ofthe fibre seems to be consisted to scales irregular ofshapeand slightlyoverlapping likescales offish. 3.3.2 Classification of wool 1. Merino wool: Merino sheep produce the best quality wool which is originated fromSpain. Classification by fleece 1. Lamb’s wool: The first fleece sheared from lamb about six to eight months old is known as lambs wool. This is in fine qualityand soft texture. 2. Hogget wool: Woolobtained fromsheep of12 to 14 months old that has not been previouslyshorn. 3. Pulled wool: When sheep is slaughtered for meat the wool is pulled called as pulled wool. 4. Cotty wool: Verypoor grade wool.
  • 28. Commercial GarmentTechnology104 5. Wetherwool:Anyfleececlipped after the first shearing is called weter wool. 3.4 Manufacturing of Wool Shearing Sheep are generallyshornoftheir fleeces inspring but thetime ofshearing differs indifferent parts oftheworld. Machine clippers removethe fleece faster and closer thanhand clippers. Superior woolvarietycomes fromthe sides and shoulderswhereitgrowslonger, finerandsofteristreatedasgoodqualityfleece. Wool fromthe chest ,bellyand shanks is treated as a second fleece. Preparation An average about 8 pounds of fleece is made from one sheep. Then the fibers are packed in bags or bales. The raw wool or newly sheared fleece is calledGrease woolbecauseit contains thenaturaloilofthesheep. WhenGreese wool is washed, it loses from 20 to 80% of its original weight. The grease known as yolk is widely used in the pharmaceutical industries for lanolin compounds. Sorting and grading Skilledworkersdo woolsorting. Eachgradeis determined bytype, length, fineness, elasticityand strength. Separating offibre bytouchand sight. Scouring Washing ofraw woolis analkaline solution is knownas scourcing. The woolis treatedwithwarmwater, soap, mild solutionofsoda ashor other alkali to remove dirt inthe fibres. Iftherawwoolisnotsufficientlyclearof vegetable,substanceafterscouring is put through the carbonizing bath. The fibres are then put through a dilute solution ofsulphuric or hydrochloric acid which destroys anyvegetable. This process is called as carbonizing and resultant woolis called ‘extract’. To remove the Grease and dirt in raw wool it is put through a series of naphtha balls followed by clear water to remove the naphtha. This is called naphtalation. This process improves the dye uptake propertyofwool. Garnetting Recycled woolfibres are obtained byseparatelyreducing the unused and used fibrous mass bya picking and shreddingprocess called garnetting.
  • 29. Paper - II Textile Science 105 Drying:Woolis not allowed to become absolutelydryusuallyabout 12 to 16% ofmoisture is left inwoolto conditionit for subsequent handling. Oiling:Aswoolis unmanageableafter scouring the fibreis usuallytreated with various oils including animals, vegetable, mineral or a blend of these to keep it frombeing becoming brittleo lubricate it for the spinning operation. Dyeing: If the wool is to be dyed in raw stock it is dyed at this stage. Some woolfabrics piece dyed, some are yarn or skin dyed and some are top dyed. Blending: Woolof different grades or pure wool fibres and other textile fibers maybeblended mixedtogetherat thispoint.Alltheinformationshould be present onthe labels. Carding: Thecardingprocessintroduces theclassificationofwoolenyarns andworsted yarns.It makesthe fibreparallelandsomeamount ofdirt isremoved due to straightening of fibres. Fibres are used for the worsted yarn are more straightened thanthe woolyarns. Gelling and combing: The cardedwoolwhichis to bemade into worsted yarnisput throughgillingandcombingoperations. Thegeillingprocessremoves the shorter staple and straightens the fibre. This process removes short fibres from1 to 4 inch lengthplaces the long fibre as parallelas possible and further cleans the fibre byremoving any remaining loose impurities. Drawing: Drawing is an advanced operation for worsted yarns which doubles and redoubles slivers ofwoolfibres. The process draws, drafts, twists andwindsthestockmakingsliversmorecompact andthinningtheminto slubbers. Roving: This is the final stage before spinning roving is actually a light twisting operationto hold thinslubbers intact. Spinning:Inthespinningoperationthewoolrovingisdrawnoutandtwisted into yarn. Woolen yarns are chiefly spun on the mule-Spinning machine are worsted yarns arespunonanykindofspinning machine mule, ring, cap or flyer. 3.4.1 Properties of wool Physical properties of wool Strength: It is stronger thansilk. Whenwet woollooses about 25% ofits strength. Longerthe fibre the greeter willbe the strengthofyarn. Resiliency: Woolis highlyresilient and comes to its originalshape when hanged afterwrinkled or created.
  • 30. Commercial GarmentTechnology106 Stretchability: Wool is highly elastic. It is about 10 to 30% stretched when dry and 40 to 50% when wet upon receiving pressure upon drying it readilyregainsitsoriginaldimensions. Shrink ability: Woolis resistant shrinkage. However long exposure to moisture maycause shrinkage. Effect of friction: Frictionwillsoften the woolfibre especiallywhenwet and thus isadvantageous inmaintaining smooth, soft texture offabrics. Crimps: Woolfibre is more or less wavyand has twists. This waviness is termed as‘crimp’. Finer the woolthe more willbethe crimps init. Merino wool has 30 crimps per inch while coarse woolhas one or two. Effect ofmoisture:Woolis the most hygroscopic in nature. It canabsorb upto50%ofitsweightandcarryupto 20%weight, without giving thefeelingof being wet. Upondrying it losses moisture slowlypreventing rapid evaporation thusavoidingchillingfeelto theuser. It absorbsperspirationafterviolent exercise and guards the bodyagainst suddenchange intemperature. Heat conductivity: Woolfibre is a part is a poor conductor ofheat and therefore thefabrics made fromthe fibre are considered most suitable as winter wear. Felting:Woolfibresinterlockandcontract whenexposedto heat, moisture, and pressure. The scale like exterior of the fibres contributes to felting. The fibres get softenedinweak alkaline solutionsdue to expansionofscales at their free edges, withfriction and pressure theyagain interlock to forma felt. This property is used in making felts for hats, shoes, floor-coverings and sound proofingpurposes. Effect of heat: Low heat has no effect but strong heat weakens the fibre and destroys the colour ofthe fibre. Chemical properties Actionofacids:Diluteacidshavelittleeffect but eitherhotorconcentrated acids weaken or dissolve the woolfibres. Action of alkalis: Alkalis tend to make while wool yellowish, strong solutionsofsodiumcarbonatewhenheateddestroys thefibre sodiumhydroxide ishighlyinjurioustothewoolfibre.Howeverboraxandammoniahavenoharmful influenceonwool.
  • 31. Paper - II Textile Science 107 Action of bleaching agents: Strong bleaching agents like hypochlorite have harmfuleffects on wool., potassiumpermanganate, sodiumperoxide and hydrogenperoxidehowever cansafelybeused for bleaching andstainremoval. Effects of moth and mildew : Wool is easilydamaged by moths that is whyduringstorageofwoolengarmentsspecialcaseisneeded.Howevermildews donot effects garments. Finishesgiventowool:Felting,fulling, mothproofing,crabbing, decanting, londonshrinking, napping, singeing and steaming. Wool blends: Woolpolyster, woolacrylic, woolnylon, silk and wool. 3.4.2 Uses of wool The majorityofwool(72.8%) is used in apparel, home furnishing account for 15-45%, industrialuses 6 to 7% and exports 5%, woolaccounts for 3.3% ofallfibres for apparel. The mostimportant useofwoolis forapparelcoats, jackets, suits, dresses, skirts, slacksmade fromwovenfabricsofvarying weights andknitted fabrics’. Allthese givesthe warmthgarments and withgood tailored look. In the home furnishing area the major use of wool is in carpets and rugs where woolis used more, cover to the carpets andwarmin the rugs. Blends of different syntheticfibreswithwoolforsuitingmaterialsareincreasinglyimportant. This result infabrics that are more appropriate inwarmer conditions. Polyester is the most important fibre used inblending withwool. Conclusion Selection of a fibre, should be willing to payfor weaving quality. Agood quality fibre (either silk or wool) is not cheap and priecs are tending to rise. Blends offibres with man made and naturalfibres have grown in importance. The consumer should read the percentage of each fibre and selling point on label. I. Test your understanding State whetherthe following statements aretrue or false 1. Silk fibre is the longest ofallnaturalfibres. ( T / F ) 2. Theprocess ofunwinding the filament fromthe cocoonis called as spinning. ( T / F ) 3. Silk has great affinityfor dyes.Acid dyes produce brilliant shades on silk. ( T / F )
  • 32. Commercial GarmentTechnology108 4. Wild silk has uneven structure and is some what dark compared to cultivated silk. ( T / F ) 5. Silk fabrics deteriorate and coloris also affected due to perspiration. ( T / F ) II. Test yourunderstanding-2 State whetherthe following statements aretrue or false 1. Gradeofwoolisdeterminedbytype, length, fineness,elasticityoflength ( T / F ) 2. Washing ofraw woolinalkaline solution is knownas reeling. ( T / F ) 3. Woolis non hygroscopic innature. ( T / F ) 4. Woolfibres interlock and contract when exposed to heat moisture and pressure. ( T / F ) 5. Bleaching agents have no effect on wool. ( T / F ) 6. Wool can be blended bypolster, acrylic, nylon etc. Short Answer Type Questions 1. What is filament fibre? 2. What are the physical properties ofsilk? 3. What is the microscopic appearance of silk? 4. What are the uses of silk? 5. What is the microscopic appearance of wool? 6. Write theclassificationofwool? 7. What are the uses of wool? 8. What are the physical properties ofwool? Long Answer Type Questions 1. What are the chemicalproperties ofsilk? 2. Write the process ofmanufacturing silk fibre? 3. What are the various types of silk? 4. How do you manufacture woolfibre?
  • 33. Paper - II Textile Science 109 5. What are the chemicalproperties ofwool?Write any4 chemical properties in detail? Answer for test your understanding - I 1. True 2. False (reeling) 3. True 4. True 5. True . Answer for test your understanding - II 1. True 2. False (scoring). 3. False 4. True 5. False (strong bleaching agents like hypochlorite haveeffect on wool. 6. True.
  • 34. Commercial GarmentTechnology110 Structure 4.0Introduction 4.1 Rayon Fiber 4.2 Polyster Fiber Learning Objectives After studyingthis unit, you willbe able to; • Understand the manufacturing process ofRayon • Identifythe structureofrayon fiber. • Describe thephysicaland chemicalproperties ofrayon • State the uses ofthe rayon • State the types ofpolyester yarn • Understand the manufacturingprocess ofpolyester • Explainthephysicaland chemicalproperties ofpolyester yarn • Classifythe types ofrayon. Manufactured Fibres 4UNIT
  • 35. Paper - II Textile Science 111 Unit Preview This unit givesus the informationregarding themanufacture andproperties ofman-made fibers. (1) Rayon (2) Polyester. 4.0 Introduction A rayon fiber was the first man-made composed of pure cellulose the substance ofwhichis themanconstituentofcellwallsoftreesandcotton. Rayon fibers are made from cellulose that has been reformed or regenerated. Consequently, these fibers are identified as “regenerated cellulose fibers”. Because ofits lustre and soft hand feel, it resembledsilk and came to be known as “artificialsilk”. However it ismore like cottoninits chemicalcomposition 4.1 Rayon History of Rayon Robert Hooke, theEnglish naturalist, had prophesied the production ofa fibersuchasrayon, thefirstofthe manmadefiberslongago in1664. Hebelieved thatitwaspossibleto makean“artificialglutinouscomposition”muchresembling, if not fully like silk worm secretion George Audemars, a Swiss chemist, discovered howto make cellulose nitrate. In1884, count Hilairede chardonnet produced the first man made textile fibersfromnitro cellulose. He is known as “father of Rayon”. Wood Rayonis produced in manyways. Viscose Rayonis popular among customers. It is made frompulp and cottonlinters. The otheris cellulose rayon (acetate rayon) in the chemist terminology, rayon and acetate arenot synthetic because natural materials- cotton, linters and wood pulp are used in their manufacture, ratherthanchemicalelements. 4.1.1 Source of Rayon Rayon is an artificial, man-made or synthetic fibre made from cellulose. Commercially rayon was produced about 48 years back. Rayon produced at that timewas verylustrous theywere given this name which means “reflecting the raysofsun”. Themainobjectiveinmanufacturingrayonwasto provideacheapsubstitute for silk. India has been importing rayon fabrics and rayonyarn.
  • 36. Commercial GarmentTechnology112 4.1.2 Structure orRayon When seen under microscope, the fiber appears smooth and rounded. Viscoserayonfibersarerodlikewithnumerous,longitudinal, threadlikestriations or lines. These are due to the indentations offiber surface. Fig. 4.1 Microscopic structure of Viscose Rayon 4.1.3 Manufacture of Rayons All types of rayon are made from cellulose. There are main four main procedures bywhichcellulose is transformed into rayon. Theyare (1) Thenitrocellulose process (2) Thecuprammoniumprocess (3) The viscose process (4) Thecellulose acetate process. The generalprinciplesofrayonyarnproductioninvolvethefollowing steps. (a)To treat cellulosechemicallyfor rendering fromit a liquid (b)To force theliquidthroughfine holes (c)To changefromliquid streaminto solid cellulose filaments. The Viscose Process This is discovered in 1892 in England. In this process Spruce, a type of treechipsareused. Sprucelogsarereducedtowoodpulpandpurifiedforcellulose base. Wood pulpistreatedwithcausticsoda to formalkalicellulose. It is treated with carbon disulphide to form cellulose xanthate. This is dissolved in dilute
  • 37. Paper - II Textile Science 113 caustic soda solution.Areddishor orangeliquid is formed. Thisliquid is filtered and then kept for ageing untila thick fluid is formed whichis called ‘Viscose’. This fluidisforcedthroughfinejets into a dilutesolutionofsulphuricacid. Inthis waycellulose is regenerated into continuous fibers. The largest production of rayon today is manufactured by this process. The cost is low. 4.1.4 Properties of Rayon Fabrics The development ofman-made fibers possessing along withthe prized qualities ofthenaturalfiber is a tributeto humaningenuity. Characteristics of Rayon Fabric · HighlyAbsorbent · Soft and comfortable · Easyto dye · Drapes well Physical Properties Strength :Thetensile strengthofviscoserayonis greaterthanthat ofwool but is onlyhalfas great as silk. Viscose rayonis also weaker thancottonand its strengthis reducedto 40 to 70percent whenwet.Yet it produces fairlydurable, economical and serviceable fabric whose smoothness of surface favorably withstands withfrictionofwear Elasticity : Viscose rayonhas greater elasticitythan cottonbut less than wool and silk. While viscose rayon fabrics have some inherent extensibility, undue strainmight cause themto sag or even burst. Cellulose Steeping Dissolving Xanthation Filtration Extrusion
  • 38. Commercial GarmentTechnology114 Resilience : Viscose rayonlacks the resilience. It should be remembered that the resistance ofa fabric to creasing depends on the kind of yarn, weave and finishing process. Drapability : Viscose rayon possesses a marked quality of drapability because it is relativelyheavyweight fabric. Heat Conductivity : Viscose rayon is a good conductor of heat and is therefore appropriate forsummer clothing like cotton. Absorbency :Viscose rayon is one ofthe most absorbent ofalltextiles. It is moreabsorbent than cotton or linen, but less thanwooland silk. Cleanliness and Washability Because of smoothness, Viscose rayon fiber helps to produce hygeinic fabrics that shed dirt. Since Viscose rayons temporarilylooses strength when wet, it must be handled withcare when washed. Reaction to Bleaches : Household bleaches containing sodium hypo chlorite, sodiumperborateor hydrogen peroxide maybe safelyused. Shrinkage :Viscose rayonfabrics tend to shrink morethancottonfabrics. SpunViscose rayon fabrics shrink more, which can be givena shrink resistant finish, suchas Sanforset. Effect ofHeat :Viscoserayonis purecellulose fiber whichburnsas cotton. Whenironing, onlymoderatelyhot temperature must be used. Chemical Properties Resistance to Mildew : Like cotton, Viscose rayon have tendency to mildew. Suchfabrics should not beallowed to remainindamp conditions. Reaction to Alkaline : Concentrated solutions of alkalies disintegrate Viscose rayon.Amild soap withlukewarmwater is recommended in washing rayons. Reaction toAcids : Beingpure cellulose, thefabric is disintegratedbyhot dilute and coldconcentrated acids similar to that ofcotton. Affinity of Dyes : Viscose rayon fabrics absorb dye evenly and can be dyed with a varietyofdyes, like acid, chrome, and disperse. Resistance to Perspiration : It is fairly resistant to deterioration from perspiration.
  • 39. Paper - II Textile Science 115 4.1.5 Uses of Rayon Fiber Apparel:Accessories, blouses, dresses, jackets, lingerie, linings, millinery, slacks, sports shirt, sportswear, suit, ties, work clothes. Home Furnishings : Bed spreads, blankets, curtains, draperies, sheets, slipcovers, tableclothes, upholstery. Industrial Uses : Industrial products, medical products, non-woven products. Other Uses : Feminine hygiene products. It’s used inindustrialwipes, medicalsupplies, including bandages, diapers, sanitarynapkin, andtampons in non-woven fabrics. 4.2 Polyester Fiber Polyester is a synthetic fiber invented in 1941. The first polyester fiber is known as‘Dacron’inAmerica and ‘Terylene’inBritain. Latervarious types of polyesters are produced. Terylene fiber is made by synthesizing terephthalic acid and ethylene glycol. The ground work for development of polyester fiber is done by W.H. Carothers. Polyester fiber is the long chain polymer produced from elements derived fromcoal, air, water andpetroleum. Polyester is a thermoplastic fiber and has good strength. It melts in flame and forms a grey hard non-crushable bead. It is an easy care fabric and can be easily washed. Polyesterfiberlooks like asmooth,glassrod similarto Nylon. Ifdelustered it shows black spotted appearance. The length, width, shape and luster of the polyester fibers arecontrolled during manufacture to suit a specific enduse. It is mostlyblended with other fibers to improve its absorbencyandto lower static electricity. 4.2.1 Method of Manufacture Generally each companyproduces its own varietyof polyester through there are likelymodifications under specific trademarks. Eg : PET (Principle raw materialis ethylene diamine and terepthalic acid) obtained frpmpetroleumand PCDT polyester. Spinning ofFiber Themoltenpolymerisrigourouslymaintainedatairtightcondition, asoxygen willaffect its stability. The viscous melt is extruded throughspinneret, and the
  • 40. Commercial GarmentTechnology116 filaments are subsequently drawn into desired polyester fiber. Variations in production process depends on desired end results. Fig. 4.2 Flow chart of manufacturing process ofpolyester The holesofspinneret mayberound or modified to be trilobal, pentagonal, hexagonal or octagonal shapes so as achieve specific effects such a greater cushioningand insulativeproperties. Other properties maybeobtained withthe aid ofspecific additives givento the spinning solution. Upon extrusionofspinneret, the polyester filament does not have allthe desired characteristics because ofrandomarrangement ofpolymer molecules. The fibers are therefore drawn or elongated with the aid ofgodet wheels. The temperature conditions andthe extent to whichthe fibers are drawnto 5 times theiroriginallength. Types of PolyesterYarn The diameterofthe polyester yarnis determined by; (a)The rateextrusionoffilaments fromthe spinneret. (b)The number ofspinneret holes and therefore thenumber offilaments
  • 41. Paper - II Textile Science 117 (c)The rate of drawing of filaments. The yarn comes in a wide range of diameterand staplelengths. The yarnsare producedbasically, as monofilament, multifilament and spunand sometimes the textured yarnsare also produced. 4.2.2 Properties of Polyester Fabrics Properties of Polyester · It resistswrinkling. · It is easyto launder · It dries quickly · It’s resistantto stretching. Physical Properties Shape andAppearance : These fibers are generallyround and uniform. The fiber is partiallytransparent andwhite to slightlyoff-white incolour. Strength :The PETpolyesters are ingeneral, stronger. Polyester is found in industrialuses and the highlydurable fabrics. Elasticity : Polyesterfibers do not havehighdegree ofelasticity.Ingeneral polyester fiber is characterized as having a high degree ofstretch resistance, which means that polyester fabrics are not likely to stretch out of shape too easily. Resilience : Polyester fibers have high degree ofresilience. Not onlydoes a polyester fabric resist wrinkling whendry, it also resists wrinkling whenwet. Drapability:Fabricsofpolyesterfilament havesatisfactorydrapingquality. Polyester spunyarn is flexible andsofter, therebydraping qualityis improved. Heat Conductivity : Fabricsofpolyester filament aregoodconductors of heat. Polyesterstapledoes not providegreater insulationintheyarnsandfabrics. One ofthereasonfor apparelgreaterwarmthofpolyester isits low absorbency. Absorbency : Polyester is one of the least absorbent fibers. This low absorbencyhasimportant advantages- theywilldryveryfast, suited for water repellent purposes, such as rain wear and theydo not stain easily. Dimensional Stability : If the polyester is properly heat set, it will not shrink, norstretchwhen subjected to boiling water, boiling cleaningsolvents or ironing temperaturesthat are lower thanheat setting temperatures.
  • 42. Commercial GarmentTechnology118 Shrinkage : Polyester fabricsshrinks as muchas20 %duringwet-finishing operationsandtheyare generallyheatset inlater treatments.Theyhaveexcellent dimensionalstability. CleanlinessandWashability:Sincepolyesterfibersaregenerallysmooth, has low absorbency, manystains lie onsurface, and are easilywashed, byhand or machine but oilstains are veryhard to remove. Chemical Properties Reaction to Alkalies : At room temperature, polyesters has good resistance to weak alkalies and fair resistance to strong alkali. It reduces with increase intemperatureand alkalies concentration. Reaction toAcids : Depending upontype, polyester has good resistance to mineralandorganicacids. Highlyconcentrated solutionsat hightemperatures cause degradation. Eg:SulphuricAcid. Effects of Bleaches: Fabricsofpolyestermaybe safelybleached, because polyesters have good resistance to deterioration to household bleaches. Ifthe polyester have opticalbrightener, bleaching is not necessary. Effect of Heat: Ironing should be done at low temperature. It gets sticky at 4400 F. Effect of Light : Polyesterhas goodresistance to degradationbysunlight. Over prolonged use, gradualdeteriorationoffiber occurs. Affinity for Dyes : Polyesters are dyed with appropriate disperse, developed dyes at high temperatures producing a good range of shades and color fastness. Resistance to Perspiration : Polyesters has no loss of strength from continued contact witheither acid oralkaline perspiration. PolyesterBlends: Polyestercottonblend, polyesterwoolblend, polyester rayon, polyester silk blend, polyacetate blend, , polyester and nylon are some common blends. 4.2.3 Uses of Polyester The most important uses of the polyester is in “woven fabrics”. The blended fabrics areattractive, durable and comfortable, retain their appearance welland easycare. The first use of staple polyester was in tropicalsuiting for men’s summersuits. The suits werelight inweight andmachine washable.
  • 43. Paper - II Textile Science 119 Polyester and polyester blends are also used in home-furnishings, sheets, blankets, bed spreads, curtains that match bed spreads, mattress ticking, table clothes. They are used in upholstery fabrics; polyester carpets have a softer hand thannylon carpets. Spun yarnare used in knitted fabrics. Here polyester with cottonblends are used. The other important use where it is used is as fiber fill. Used in pillows, comforters, bedspreads, other quilted households and apparels, winter jackets etc. Non-woven fabric are the fourthimportant use ofthe polyesterfabrics eg: fusible interfacings, pillowcovers, matress interlining etc. It has many industrial uses too in pile fabrics, tents, ropes, cording, fishing line , cover stock for disposable diapers, gardenhoses, sails, seat belts, filter fabricsused inroad buildings, fertilizer bags, inmedicinalfield for artificial arteries, veins and hearts. Conclusion Consumersaremostlyawareofthefibercontent withfibresandtheirblends. The man-madefibres likerayon, polyesterto have qualitiesofstability, durability, comfort, wrinkle resistance ease ofcare etc. I. Test your understanding State whetherfollowing statements areTrueor False. (1) Rayon is the first man-made fibres made fromcellulose. (T / F) (2) Acetate rayons are rod-like with no striations. (T / F) (3) Nitrocellulose processis first used for productionofrayon fabrics. (T / F) (4) The largest production ofrayon is donebycuprammoniumprocess. (T / F) (5) Viscose rayon tend to shrink more than cotton fibers.(T / F) II. Test your understanding State whetherthe following statements areTrue or False (1) Diameter ofpolyester yarn is determined byextrusionoffilaments of spinneret, no. offilaments and rate ofdrawing filaments. (T / F) (2) Polyester fabrics are bad conductors ofheat. (T / F)
  • 44. Commercial GarmentTechnology120 (3) Polyesters is used for the water repellent purposes and willnot stain easilydue to its hygroscopic nature. (T / F) (4) Polyester is unaffected bymoths, carpet beetles, silver fishor other insects. (T / F) (5) Polyesterhas good resistance for degradation bysunlight. (T / F) Short Answer Type Questions (1) What is a man-made fiber? Who was the father ofrayon industry? (2) What is the microscopic appearance ofrayon? (3) What are the uses ofrayon? (4) What are the physical properties ofrayon? (5) What is the microscopic appearance ofpolyester? (6) What are uses ofpolyester? (7) What are the physicalproperties ofpolyester? (8)Write the drapabilityin polyester fiber? Long Answer Type Questions (1) What are the chemical properties ofrayon? (2) Write the manufacturing process ofrayonbyViscose process? (3) What are the chemicalproperties ofpolyester? (4) Write indetail, about manufacturing process ofpolyester fiber? (5) Explain theuse ofpolyester? Answer for test your understanding - I (1)True (2)False (cuprammoniumprocess) (3)True (4)False (Viscose process) (5)True
  • 45. Paper - II Textile Science 121 Answer for test your understanding - I (1) True (2) False (3) False (due to low absorbency property) (4) True (5) True
  • 46. Commercial GarmentTechnology122 Structure 5.0Introduction 5.1 Spinning andvarious types ofspinning 5.2Yarns andclassification ofyarns Learning Objectives After studying this unit, the student willbe able to • Understand about the classification ofyarns. • Know about end uses of plyyarns • Know about end uses of corded yarns • Know about noveltyyarns and types • Understand yarn-twist. • Explainthe yarncount and balance ofcloth. Unit Preview Thisunitgivesustheinformationregardingtheclassificationsofyarns, turst in the yarns, balance ofcloth yarncount and noveltyyarns. Spinning and Yarns 5UNIT
  • 47. Paper - II Textile Science 123 5.0 Introduction Spinningis theprocessofdrawingoutandtwistingofagroupor bundlesof fibres into a continuous thread or yarn of sufficient strength to be woven or knitted into fabrics. In the beginningthe yarns were spunbymane withbarehands without the aid of any tool and it must have been many centuries before the spindle was evolved for spinning. The spindle or “takli”stillsurvives as a tool hand spinning wool, silkand cotton yarn. It isthe simplest toolwhichconsistsofa rounddisc whichis attachedinthe center to a thin, smooth rod about inches long. The upper end ofthe rod has a groove or a hook whichbulkofthe fibres, these are drawn out ina long stand. The spinner while simultaneouslypulling thefibres, gives a twist to the spindle and let it go. The spindle whirl around and thus twisting up the pulled fibres makes a continuousthread. The thread is then wovenround therod above the disc. The disc provides the necessary weight which quickens increases and prolonged the revolving of the rod, therebythe twisting ofthe fibre ensures a strong thread. Who does not know the “charka” in India. Acharka is used for spinning yarninthehandloomindustryinIndia. Theyarnspunonthecharkhaisofvarious qualities.Thefamous“DaccaMuslins”whichwereuncomparablefortheirfineness but alas are extinct now were wovenofa charka yarn. The inimitable soft and light pashmina ofKashmir are stillwoven ofthe charkhaspin yarn. Charkhas are ofvarious types. In the textile industries todayelectrically driven machines are employed for spinning. Several machines are used to complete theprocess ofspinning, whichconsists ofstages suchas drawing out offibre to reduce size and to give slight twist-roving and then spinning. There are two general methods ofprocedure. In one process, the action ofdrawing, twisting and winding is continuous and this is called ‘ring’ spinning and in the other, the drawingand twisting is stoppedwhile the twisted threadis wound up (as inthe case ofhand spinning) and this is known as ‘mule spinning’. The ring spinning is a quicker process andhas the advantage ofreducing operating cost andincreaseproduction,but themulespunisfiner, softerandofgreaterevenness. In spinning yarns, whether by hand or machine a difference has to be made inthe yarn intended for warp and weft or filling. The warp yarnneeds a greater amount oftwists to produce a strong firmthread which is used for the foundationofthefabric. The yarnisgiventwistsofspecified numberofturns per inch.At first, a continuous threador a strand is made fromfibres and severalof these strands are twisted together to get a finalyarn.
  • 48. Commercial GarmentTechnology124 Dependinguponthefibres, thepreparatorymethodsofspinningareclassified into two types: (1) Chemicalspinning– filament fibres (2) Mechanicalspinning – for the short staple fibres Types of Spinning (1) Chemicalspinning Chemicalspinningoperationsaregenerallyusedtomakeman-madefilament fibers to yarns.Aviscous solution is extruded througha nozzle like die called a spinneret. Man-made fibersare made into yarns bychemicalspinning. There are three types ofchemicalspinning. Theyare (1) Wet spinning (2)Dryspinning (3)Melt spinning Wet Spinning The first commercial method for manufacture of manmade fibre is wet spinning ofcellulosic fibre-rayon. This process involves the use ofappropriate liquid solutionwhich is pumped through smallnozzle called spinneret, into a chemicalbaththat coagulatesthe extrudedsolutionofendlessstrandsoffilaments. These coagulatedcontinuous fibers are drawnout ofbath, purifiedbywashing, dried and thenwound onto spools. Theconstructionofspinneret decidesifit is a mono-filament, if one hole, Multifilament if many holes are present in the spinneret. The amount of twist givento the processed yarnwillaffect texture andstrength. DrySpinning This processinvolves use offiberliquid solutionwhichispumped through spinneret into an air chamber. The air reacts with extruded streams, of liquid Chemical Spinning Mechanical Spinning (filament fibres (Staple Fibres) Wet Dry Melt Conventional Direct
  • 49. Paper - II Textile Science 125 fiber causing them to solidify. These coagulated fibers are then drawn out of chamber, twisted, or processed then wound onto spools. Eg.Acetate Melt spinning Polyester chips obtained fromreacted chemicalcombinations are melted and thenpumped through spinneret into an air chamber. The extruded stream cools and solidifies into continuous filaments which are then drawn out from chamber twisted or processed or subsequentlywounded onto spoons. Eg. Polyester (2) MechanicalSpinning Mechanical spinning refers to a multistep procedure in which machines physicallymanipulateandspinfibresintoyarns. Therearetwotypesofmechanical spinning. Theyare(1) Conventionalspinning (2) Direct spinning Conventionalspinningis used to makeyarns fromnaturalstaplefibres and some man-made fibers. It involves series ofmachine operations. Direct spinning isused to produce staple yarnsfromfilament fibers. Conventionalspinning Basicallyconventionalspinning involves sorting andblending, formationof web for ease ofhandling, alignment offibers, stretching offiber bundles and actualspinning offibres into yarns. Sorting and Blending Picking Carding Drawing Roving Spinning Combing
  • 50. Commercial GarmentTechnology126 (1)Sorting and Blending: Thefirst stepinconventionalspinningofstaple fibers issorting and blending. Balesoffibresare loosenedand fluffed. Impurities such as dirt and leaves are removed and fibers are blended to product specifications. (2) Picking: It is thesecond step in conventionalspinning. The fibers are formed into web like sheets for ease of handling. These fiber webs are called laps. The forming ofstaple fibers into laps is called picking. (3) Carding: Thefiber webisfedinto acarding machine,whichstraightens the fibers andpartiallyarranges theminto parallelrows. Thealignedfiberwebis thenformedinto along, untwistedropecalledasliver. Theprocess ofseparating and aligning thefibers is called carding. (4) Combing: Whenonlylong, smooth staple fibers aredesired the short fibers are removed from the slivers in a combing machine. Removal of short fibers and alignment of the remaining long fibers into parallel rows is called combing. (5)As only long fibers are used, combing increases luster and strength. Thus a fabric composed of yarns than that have been combed will be more expensive thana fabric composed ofyarns that have onlybeen carded. (6) The drawing process uses four sets of rollers, each set rotating at faster rate ofthe previous set severalsliverss are combined and pulled into one long, thenslivers. Iffurther blendingisdesired, sliverss ofdifferent fibers maybe combined inthe drawing process. (7) In roving the drawnsliverss are pulled to approximatelyone fourth of their originaldiameter and slight twist is added. Hence roving is process that reduces thesliverss to a sizesuitable for spinning. (8) There are three systems ofconventionalspinning a) cottonb) woolen (c) worsted Theyutilize thesteps previouslydiscussed. Here themachineryis designed to handle specific type and lengthoffiber involved. ConventionalSpinning Cotton Woolen Worsted eg. cotton, linen eg. wool and fur eg. long fibres man made fibers fibres and staple with high length man made degree turst fibres
  • 51. Paper - II Textile Science 127 Direct spinning It is used to produce staple yarnsfromman-made filament fibers. It is less expensive.Inthedirectspinning,weblikestructuresoffilamentfibersarestretched and brokenat intervals producing long staple fibers. The staplefibers are then drawn into sliverss. The remaining spinning process is done bythe following steps. 5.2 Yarns and Classification of yarns Yarns can be classified based on length of fibres present and number of parts present.According to the lengthoffibres present in yarn. Yarn are broadlyclassified as staple/spun, yarns or continuous filament yarn. Spunyarn consist ofstaple fibre assembled and bound together bytwist to producetherequired characteristicssuchasstrength, handle andappearance. 5.2.1 SpunYarns Spunyarnsare made fromthestaple fibres that aretwisted together. Spun yarnsarecharacterizedbyprotrudingfibreends. Spunyarnsstrengthisdependent on the cohesive or the clinging power ofthe fibre and on the points ofcontact Filament fibres stretched Breaking Drawing Roving Spinning Spunyarn Filament yarn Yarn Smooth Textured bulk Napping Average Twist Voile Twist Crepe Twist
  • 52. Commercial GarmentTechnology128 resulting on pressure ofthe twist. Thegreater the number ofpoints ofcontact, the greater is the resistance to the fibre slippage withinthe yarn. Theyare suited to clothing fabric in which absorbency, bulk, warmth or cotton like or wool like textures is desired. When worn fibre ends hold the yarns awayfromclose contact fromthe skin, and so fabrics made ofspunyarn is more comfortableona hot humid daythan a fabric ofsmoothfilament yarns. Protruding ends contributeto a dullfuzzyappearance, to the sheddingoflit and to theformationofpills onthe surface ofthefabric. Theyalso get dirted readily, spun yarncanbe givendifferent types oftwist basedonthe end use as napping twist. Napping twist: This type ofyarn is called as low twist, yarn. It has 2.3 turns per inch such low twist results in lofty yarns which allow for napping of fabric. Thus napped fabrics are bulky and provides warmth when used in garments. Average Twist: It is frequentlyused for yarns made ofstaplefibres and is veryseldomusedfor filament yarns. Theamount oftwist that gives warp yarns maximumstrengthis referred to asstandard warp twist. Hard twist (Voile twist): When yarns are given 30-40 turns per inch, theyarecalled hard/voile twisted yarns. The hardness ofthe yarn results when twist brings fibres closer together and more compact. CrepeYears: Crepe yarns aremade ofwitheither stapleor filament fibre. Crepe is aFrenchword meaning crinkle. Theyare made with ahigh number of turns per inch(40-80) inserted inyarns. This makes the yarnso livelyand kinky that thetwist must be set before it canbewovenor knitted filament crepe yarns are used in fabrics like Georgette and chiffon. 5.2.2 FilamentYarns The range offilament yarns is as diverse as that ofstaple yarns. Filaments yarns are divided into two types viz flat continuous filament and textured continuousfilament yarn. (a)Continuousfilamentyarnsareprovidedfromlongcontinuousfilaments. Filaments yarns are primarilyman-made. Silk is the onlynaturalfilament and accounts for less than 1% of the fibre and yarn production. Regular or conventional filaments yarns are smooth and silk like as they come from the spinneret. Their smoothnature gives themmore luster thanspunyarns, but the luster varies withthe amount ofthedelusturing agent used inthe fibre spinning solutionand theamount oftwist inthe yarn. Filament yarnshave no protruding
  • 53. Paper - II Textile Science 129 ends, so theydo not shed lint; they resist pilling and fabrics made from them tend to shed soileasily. (b) Textured continuous yarn are man-made continuous filament yarns that are been modified by subsequent processing to introduce crimps, coils, loops or other distortions into the filament or with high twist or low twist. The additionoftwist increases bulk texturing gives slipperyfilaments the aesthetic propertyofspunyarns byalteringthe surface characteristics and creating space between the fibres. It also improves the thermal and moisture absorption of filament yarns. According to the numberofparts inYarns 1. SimpleYarn. Intheconstructionofsimpleyarn, onlyonekindoffibreisused. Themanner inwhichthefibres are twistedwillbethesamethroughout the lengthofthe yarn. Yarns are knownas simple, plyor cable depending uponthenumber ofstrands theycontain. 2. SingleYarn Inthis, anumberoffibresaretwistedtogetherinto acontinuouslength. The yarns consists of one kind offibre. This type ofyarnis the oneusuallyfound in most standard fabrics for clothing and householduse and purposes. (a) Single yarn (b) Two ply yarn (c) Cord yarn Fig. 5.1Types ofYarns 3. Ply yarn Two or morethantwo single yarnsare twisted together to forma plyyarn. These yarns areknown as multiple strand yarn. Iftwo single yarns are twisted together, theresultingyarnisknownastwo-plyyarn. Ifthreearetwistedtogether three-plyyarnand so-on.
  • 54. Commercial GarmentTechnology130 4. Cord/Cable It is made by a third twisted operation, in which ply yarns are twisted together. Some types of sewing threads and some ropes belong to this group. Cords are seldomused in apparelfabric, but used inindustrialweight fabrics. Fig. 5.2 Parts ofYarn DoubleYarn This consists oftwo or more single strands treated as one in the weaving process, but the strands are not twistedtogether. These areused for ornamental effect as the low twist yarns produce luster and softness. 5.2.3 Novelty Yarns The constructionofthese yarns is ofcomplexnature and is varied inmany ways. These yarnsare usuallyplyyarnsofdifferent kindsoffibresor ofdifferent colours and are irregular rather thansmooth single strand or yarn ofvarious colours, sizesoffibres maybetwisted together to formcomplex yarn.Another varietyisbrought about inthiskind ofyarnbyvarying the tensionorspeed after intervals ofcertainlength. Thus allowing one part to loop or twist around the other. Noveltyyarnsarealso constructedfromsimpleyarnbyvaryingtheamount oftwist. The complextype ofnoveltyyarn is used withtwo objects inview one is to combine different fibres eg. Cotton and rayon may be blended with or covered bywoolor silk. This lowersthecost ofproduction. The other objective is to producea noveltyyarn. Forthe construction ofnoveltyyarns, at least one Binder Ground Effect
  • 55. Paper - II Textile Science 131 or two single yarns are use. One forms the foundationyarn knownas a base or the core and the other, The effect ofyarn whichis wound or looped round the first one.Athird yarn called binder yarn is oftenused to fasten or tie the effect yarn to the foundation yarn. These types ofyarns are mostlyused for drapery, up hoisteryfabrics. Fig. 5.3Parts of NoveltyYarn 5.2.4 Types of Novelty Yarns Slubyarn: This is a yarn made withthick and thin placing byvarying the amount oftwist in the yarn at regular intervals. Theyare found in draperyand upholsteryfabrics. Fig. 5.4 Slub yarn Flock yarn: These are frequentlycalled as flake yarns. These are usually single yarns inwhich smallamount offibres either different colours or luster or bothareinserted into the yarnand held inplace bytwist ofbaseyarn eg: tweed fabric. This gives a spotted and short streakyappearance. Fig. 5.5 Flock yarn Thick and thin yarns: These aresimilar to slubyarns but theseare made fromfilament like slubprepared fromstaples. The pressure forcingthe spinning solutionis varied the filament is thick in some places and thin insome. Fig. 5.6Thick and thin yarn Core yarn Boucle yarn Effect yarn
  • 56. Commercial GarmentTechnology132 BoucleYarn: These are characterized by a projecting fromthe body of the yarnat fairlyregular intervals. Thereare 3 plyyarns. Theeffect yarns forms irregular waysurface and binder ties it to the base. It has twisted core yarn. Fig. 5.7 BoucleYarn Loop and curlyarn, Gimp yarn: Gimp is same as boucle but the effect yarn isregular semicircular appearance, while in loop. Snarl yarn or spike yarn: This is made in the same way as loop yarn using ahighlytwisted effect yarn, whichforms snarls ratherthanloops. Knop(button)yarn/knot/Nub/Spotyarn:Thisfeatureprominentbunches ofone or more ofthe component yarn at regular or irregular intervals. This is madeonaspecialmachine that permitsthe baseyarnto beheldalmost stationary while the effect yarn is wrapped around it severaltimes to build upon enlarged segment with brightlycoloured fibres added at the enlarged spot. Fig. 5.8 Knopyarn SeedorSplash: Theyresembleknops or knotyarnsbut theknot segments are tinyinseed yarn and elongated in splash yarn. Cloud: Atwo colouredyarn, inwhichbothyarns takeinturnto obscure or cloud the other, giving the appearance ofanintermittent color change. Spiral or Corkscrew : It is made bytwisting together two plyyarns that differ insize, type or twist. These two parts maybe delivered to the twister at different rates ofspeed. Fig. 5.9 Spiral yarn Boucle yarn
  • 57. Paper - II Textile Science 133 Chenille Yarn: These create specialeffects chenille means caterpillar in French. The yarn has a cut pile effect which is bound to the core on the loom warps are arranged in groups (2-6) which are interlaced in a cross weaving manner. Weft is inserted in a normal manner. These are cut into wrap way threads. Fig. 5.10 ChenilleYarn MetallicYarn: These are primarilydecorative. The plastic coasting on it resists tarnishing but care must be takenwhile pressing as puremetals are soft, their thinfilms are used overa core yarnthat has replaced gold and slivers now. There are two methods ofpressing. Yarn twist: Twist isthe spiralarrangement ofthe fibres around theaxis of theyarn.Revolvingoneendofthefibrestrandwhiletheotherendisheldstationary produces twist.Twist binds the fibrestogether and gives thespunyarnstrength. It isa wayto varythe appearance offabrics. The number oftwistsis referred to as turns per inch. Theyhave a direct bearing onthe cost. Twist is the spiralarrangement of the fibres around the axis of the yarn. Revolving one endofthe fibre strand while the other end is held stationaryany produces twist. Twist binds the fibres together and to gives the yarn. Higher twist whichyields lower productivity. Fig. 5.11Yarn twist Direction of Twist The direction of twist is described as s-twist and z-twist. Ayarn has S- twist ifwhenheld ina verticalposition, the spiralconfirmthedirection ofslope
  • 58. Commercial GarmentTechnology134 of the centralportion of the letter “Z”. Z-twist is the standard twist used for weaving yarns. The majorityofsingleyarns are spunwithtwist in Z-direction. TheAmount ofTwist varies with 1. The lengthoffibres 2. The size ofthe yarn 3. The intended use 5.2.5 Yarn count Yarnnumber variesand it differsaccordingto the kind offibre. Manyyarns are used for weaving and sewing threads are numbered bythe cotton system. Spunyarnsize is referred to as count and isexpressed interms oflengthper unit ofweight. It is anindirect system. The finer theyarn, the larger thenumber. The count is basedonthe number ofhanks (1 hank is840 yards) in1pound ofyarn. Inthissystemthe unit ofweight remains constant. Count = length/ one pound. Count = No of hanks x 840 yards / one pound. Denier: Filament yarnsize is dependentlypart on the size ofthe holes in the spinneret and partlyonthe rateat whichthe solutionispumped throughthe spinneret and rate at whichit is withdrawn. The sizeofthe filament yarns isdetermined as denier, whichis expressed in terms ofweight per unit length. If9000 meters ofyarnweigh 1 gmit is then 1 denier. Inthissystem, the unit oflengthremains constant. The finertheyarn, the smaller the number. Denier = weight ofyarns ingms/9000 mts. 1 denier = 9000 mts weigh 1gm Texsystem:The internationalorganizationforstandardizationhasadopted theTexsystem, whichdetermines the yarncount or number inthesame wayfor allfibre yarns and uses metric units. Tex= weight in gms/100 mts ofyarn. Conclusion Therearedifferent typesofyarn.Eachhavingtheowncharacteristics. These characteristics varyaccordingto the constructionand the treatment giveninthe manufacture ofthe yarn. Yarns playa very important role in determining the hand and performanceofthefabric.Yarnis the generic namefor the assemblage
  • 59. Paper - II Textile Science 135 offibres that is laid downortwisted together. Thus yarns playanimportant role inthetextileindustry. I. Test your understanding State whetherthe following statements aretrue or false 1. The threetypes ofspinning are wet, dryand melt spinning in chemical spinning. 2. Dryspinning is used to make polyester. 3. The construction ofspinneret decides the diameter ofthefiber and the type offibrei.e. mono filament and multifilament depending onnumber ofholes. 4. Conventionalspinningutilizes the steps discussed for (a) Cotton (b) Wool (c) Worsted fibers too. 5. Direct spinning is used to produce staple yarns fromnaturalfibres. II. Test your understanding State whether thefollowing statement areTrue/False 1. The warp yarn needs a greater amount oftwist to produce strong firm thread (T/F). 2. Spunyarnconsists offilament fibres (T/F). 3. Napping can done to low-twist yarns. (T/F). 4. Crepe is French word meaning crinckle (T/F). 5. In simple yarn one kind offibre is used. (T/F). 6. Whentwo or more thantwo single yarns are twisted together,it is called cable (T/F). III. Test your understanding State whether thefollowing statements areTrue/False 1. Noveltyyarnsare mostlyused for upholstery, drapery. (T/F) 2. Twist isthe spiralarrangement offibres around the axis ofthe yarn. (T/F) 3. The direction ofthe twist is described as X-twist andY-twist. (T/F) 4. The count is based on number ofhanks in 1 pound of yarn. (T/F)
  • 60. Commercial GarmentTechnology136 5. Denier –Weight ofyarns ingms/1000 mts (T/F). Short Answer Type Questions 1. What is yarn? 2. What are spun yarn. 3. Write about continuous filament yarns. 4. Write about noveltyyarns. 5. What is yarn twist. 6. What is yarn count? 7. Write about tex system. Long Answer Type Questions 1. Write the classification ofyarns. 2. What is filament yarn?Write about textured continuous yarns. 3. What are noveltyyarn?Write anyfour types ofnoveltyyarns. Answers for test your understanding - I (1)True (2) False (acetate) (3)True (4)True (5) False (man-made fibres) Answers for test your understanding - II 1. True 2. False – Staple fibres 3. True 4. True 5. True 6. False – Ply yarn
  • 61. Paper - II Textile Science 137 Answers for test your understanding - III 1. True 2. True 3. False – S & Z twists 4. True 5. False – 9000 mts. 4. Write indetailabout yarntwist.
  • 62. Commercial GarmentTechnology138 Structure 6.0Introduction 6.1 Weaving 6.2Knitting 6.3 NonWoven fabrics Learning Objectives • Understand what is weaving • Understand the generalcategories ofnonwovens a) durable b) disposables • Explainthesemidurable wovens. • Know about a)Weft knitting b)Warp knitting • Classificationofweft knit fabrics • Design inweft knit fabrics • Identificationofwarp knits. Fabric Construction Methods 6UNIT
  • 63. Paper - II Textile Science 139 Unit Preview Thisunit givesus theinformationregarding thefabricconstructionmethods such as (a) Weaving (b) Knitting (c) Non woven fabrics. 6.0 Introduction Fabrics are producedmostlyfromyarns. Few fabricsare directlyproduced from fibers. In Indian market 70% of the fabrics are produced by weaving. Amongtheotherfabricsthat isnonwovenfabricslacemakingisworthmentioning along withneedle punched and tufted fabrics. Felts are fabrics made directly fromfibers without making yarns where fusible use is mostlyemerging now a day. The fabric construction process determines the appearance and texture the performance during use and care and cost of fabrics. The process often determines the name ofthe fabric for eg: felt lace, double knitt and jersey. The cost offabrics inrelation to the constructionprocess dependsuponthe number of steps involved and the speed ofprocess, the fewer the steps the faster the process, the cheaper is the fabric. The fabric constructionmethods include weaving, knittingand nonwoven fabrics. 6.1 Weaving Yarn isturned into fabricsofgarments byweaving, knitting, or felting. Fabrics are woveninlong lengths from40 to 100 or moreyards and from about 20 to 60 inches in width. For a fabric to have strength and compactness combined with a fair degree ofelasticity, the warp and filling threads must be interlaced. This interlacing is called weavingand it is doneona loom. An interlacing where the filling threads are passed alternatively over and under thewarp threads is calledas a plainweave. It is the simplest ofallweaves. Ifthe fillingsthreads are passedoneover and2 under ormore warp threads willresult intwillfabrics.Thesurfaceofsuchfabrichaspatternofparalleldiagonal ridges.
  • 64. Commercial GarmentTechnology140 Ifthe warp threads or filling threads are considerablythicker then the rib- weave is produced. Thus the verylarge number of variations of methods for interlacing the warp and filling threads makes to weave the wide variety of fabrics each of which has specialproperties and uses. The beam of the warp threads is placed at the back of the loom and the threads are drawn from it across the loomfromback to front to be wound on another roller. Forthe weaving ofplaincloth, the threads aredrawnthroughthe eyes oftwo sets ofheddles. The filling threads pass over and under alternate warp threads which are lifted and loweredbythe corresponding heddles. Toe cop with the filling threads is placed in a shuttle which is moved or thrownfromside to sideacrossthe loom. Eachpassoftheshuttle laysonefilling threads. Thecomblike reed describedearlierbeatsthefillingthreadstight against thepreceedingfillthreads, asthefabricis wovenitis slowlywoundonto a roller infront ofthe loom. The following listsincludes some ofthemost commonweaves: 1. Plain weave (a) Rib weaves (b) Basket weave 2. Floating weave (a) Twillweave (b) Satin weave (c) Sateen weave. And its variations 6.2 Knitting The knittingsindustryisa uniqueanddistinct part ofthetextileindustry. It is the second important method of making fabrics after weaving. The knit characteristics are • Bulkywithsurface effect. • Looselyknittedor tightlyknitted. • Rib-purl-tricot. Circularknit:Anyfabric produced on acircular knitting machine. Double knit:Aspecialtype ofribknit fabric usuallyclosedstitched witha pattern or design effect, generallythicker, heavier and more stable than jersey.
  • 65. Paper - II Textile Science 141 Difference betweenWeaving and Knitting Weaving and knitting are the two most common process ofmaking cloth. Weaving is the process of interlacing two sets of yarn at right angles. This operation is done either on a hand or a power loom. Ifone set of yarns form loops one loop caught into another and one row ofloops hanging on the one below. The cloth is made byknitting.Of these two processes, Weaving is the most common method although new and improved knitting machines make clothquicklysatisfactoryand the attractive patterns. Wales (in knitting’s): Aseriesofloops insuccessive rowslyinglengththe wise ofthe fabric. Purl: Purlis actuallythe opposite ofknit. Fig. 6.1 Plain stich and purl stitch Course: Aseries ofstitches or loops that run cross wise is knitted fabric, corresponds to the fillings inwovengoods. Stitch:Asingle loop or turnofthread oryarnmade byhandor machine in sewing crocheting, tatting , lace making,knittingand knotting. Jersey: Describes any knitted fabrics where in all of the stitches on one side ofthe fabric are knit stitches, while allstitchesonthe reverse sideare either purlstitches or a combination ofpurltuck and /or miss stitches also known as singlestitches. The knitting industryhas two mainbranches (a) The knitted yarnsgoods industry : Whichproduces thefabric sold to apparelmanufactures, sewing centre retailshops and others.
  • 66. Commercial GarmentTechnology142 (b) The knitted end produces products industry: Which produces completed consumer products such as hosiery, sweaters, men’s T shirts and athletic shirtsand others. Weft knitting: Knits are classified as a) warp knits b) Weft knits. It is a type of knitting in which yarns run horizontally from side to side across the widthofthe fabrics. The fabricis actuallyformed bymanipulating the knitting needlesto make the loops in horizontal courses built one on top of another. All stitches in a course are made byone yarn. It is simplest form;a weft knit canbe made from one yarn. Weft knits are made either flat or open width fabrics (like woven fabrics) onso calledflat knitting machines. Fig. 6.2 Simple warpknit fabric Warp knitting:Warp knitting’sinvolvesthe preparationand useofa warp beamcontaining averylarge number ofparallelyarns mounted on the knitting machine. In warp knit fabrics the yarn run the length of the fabrics. The yarn forms the verticalloop in the one course and theymove diagonallyto the next wale to make a loop inthe following coarses. Theyarnzigzag fromsideto side along thelengthofthe fabrics. Eachstitch ina coarse is made bydifferent yarn. Knit fabrics names: Classical knit fabrics are named primarily on the basis oftheir constructionnot onthe basis ofappearance and weight. Identification ofwarp knits Practicallyallthe warp knittedfabrics are identifiedanddistinguishedfrom weft knitted materialsbycarefulobservation ofthe face and backofthe fabric
  • 67. Paper - II Textile Science 143 usually with the aid of a pick glass. The face of the fabric has rather clearly defined plainstitches. Generallyrunning verticallybut slightlyangled fromside to side. The back of the fabric has slightlyangled but horizontal floats. These floats are called ‘laps or under laps’ formed fromthe side ways movement of the warp yarns as the fabric is made, the recognition oflaps ina knitted fabric isthemost important distinguishing feature. 6.3 Non woven fabrics Non wovenfabrics are made bythe anyprocess otherthanweaving. They are defined as textile materials made directlyfrom fibers and held together as fabrics bydifferent methods. The firstnonwovenwasintroducedin1942. There are two generallycategories ofnon woven’s 1. Durable 2. Disposable. Durable: The materials are not manufactured or intended to be thrown awayafterthesingleorlimitednumberofapplications. Examplesincludeapparel interlining, carpet backings etc. Disposable: these materials are manufactured with the intention ofbeing thrownawayafterthesingle orlimitednumberofapplications. Examplesinclude disposable diapers, head rests, surgicalgowns, filters etc. Semi durable non wovens: Some items might be considered as semi durable like handwipes. The major fiber used innonwovensfor the disposable is rayonwhilethe major fibersfor durables include rayon, polyster, olefinothers used are nylon, vinyl, acrylic, cottonforcreating non woven’s a weboffibers is first made. This means that fibers are laid by machines in random manner to form this layer called web. Later these webs are laid over each other and are then hold in place by - Needle punching - Bonding bymeans ofadhesive heat. Needle punching is a mechanicalprocess which enlarges the fibers in the web bypunchingthemwithneedles. Thisis the most inexpensive method such non wovenare used infloorcovering in filters. Bonding is a method where 2 or 3 more layers offiber webs are made to stick to each other by adhesives. These are used in disposable items such as protective gowns, hats etc. Bonding bymeansofheat canbedone whenthe fibre webscontainat least 30% fibers. Since these synthetics soften by heat, heat is applied so that the
  • 68. Commercial GarmentTechnology144 fibers bond with each others forming a non woven. These non woven provide shape to cut parts ofgarments. So this webs can be used ad interlinings. Felting Woolis aprobablymost idealforfeltingbecausethefibersswellinmoisture, interlock andremainin the conditionwhenpressed and shrunkwhen the fibers have been selected and if necessaryblended with cotton or man made fibers theyare caredinto a flat sheet or bat. Bats areplaced first one wayand thenthe other layers untilthe desired thicknessisreached.Allowance has to be made for shrinkage because steam and pressure of heavy pressures in the process of felting mayincreasethe bats as muchas 20% thickness. To makethe felt fabric stronger and morecompact the fabrics is placed inwarmsoapywater where it is pounded and twisted. For heavy felt a weal acid is used instead of warm soapywater.The clothis thenreadyfor finishing processconsistingofscouring, dyeingpossiblypressingorshearingandtreatment withspecialfunctionalfinishes to make it water repellent mothproofand shrinks create andfine resistant. Felt is made for men and a women’s hat’s, women’s skirts, rests and slipper tables covers. Paddlingandlining’s wovenfeltshavetheirplaceprimarilyintheindustrial field. Nets and braids Net in geometrically shaped figured mesh fabric made of silk, cotton , nylon, polyester, rayonand other man made fiber. It comes indifferent sizes of mesh and in various weights. On the other hand machine made net is closely related to warp knitting because it is constructed on either a tricot or Rachel warp knitting machine. The first nets to be made by machine were the warp knitted tricot that appears about the middle ofthe 18th century. Another type of net in the knotted square mesh type with knots with 4 corners to formthe mesh. Originallymade byhand and used byfisherman it is now made by machine. These modernfish nets of linen cotton byman made fibers are used for glass curtaining in contemporaryliving rooms, sun porches and dens. Braids This is a method of interlacing 3 or more yarns or bias cut strips of cloth over andunderone anotherto forma flat ortabularfabric. Thesebraidedtextiles bands whicharerelativelynarrow can be used as belts, pullcards for lights and for trimming for uniforms and dress tapes for pajamas’ and some shoe laces. Severalwidth ofplastic and straw braidingcan be sewentogether to make hat
  • 69. Paper - II Textile Science 145 shapes similarly by braids of fabrics or yarns may be sewn together to make braided rugs. Felt: Felt is the oldest knowntextile. Wooland related animalfibers such as camel, goat, and hair haveunique feature ofenlargement when subjected to heat, moistureand rubbing agitation. Thispropertyis the base offelt fabric. lt ismade directlyfromfiberstreated inmachines designedto accomplish thefeltingaction(heat, moisture andagitation).Despiteofwool, rayonorcotton can also be used. Felt does not fray or ravel. It can be blocked to shape in all directions becauseit hasnogain. It hasgoodexcellent shockabsorbingandsoundabsorbing tendencies. It haspoor drapabilityand lowtensile strength it cannot be tornbut onlybe cut like woven fabrics it has no gain. Lace fabrics: Lace isa fabric consisting ofdecorativedesigncreated with thread s or yarns on a net like open background. They may be full of fabric widthwhen used in making dresses or evening wear etc. (a)Trimming laces:Awide varietyofpatterns available inlaces used for trimming. Theyare produced having narrow width ranging from1cmor less width. Theyare available at various costs and available at therange ofaverage consumer.Theyareused asdecorative materials, apparels, householdmaterials. (b) Nylon net laces: These laces generallycontain a net background on whichpatternsaremade. Theyaremachine made, lessexpensiveandare mostly used as curtains. The elasticitypose difficultyincuttingand stitching. The patternshould be properlyplaced over the fabric, taking care not to stretch the fabric and while cutting also avoidsthe stretching offabrics. As the lace fabrics are delicate they require gentle handling sewing and care. Handsewing is most commonlyemployed as machinepuckerthe lace and makesitunsightly. Handwashingismostlyrecommendedto preservethedelicacy oflacefabric.Amild detergentshould be employed whilewashing these fabrics. It isthemost complicatedofalltextilemakingprocesses.Theyareconsidered as fabrics ofluxuryand delicacythough someare machine washable. Theleavers’machineproducesthemostfinest andmost intricateofmachine made laces. Theyare ofspecific style, type or range weight.
  • 70. Commercial GarmentTechnology146 Tuftedfabrics:Itisanothertypeofthepilefabricsnotproducedbyweaving or knitting. Tufted fabrics are produced byneedling extra yarninto an already wovenfabricofa relativelyopenweave construction. Machinefortuftingare multi-needlemachinesandarecapable ofproducing a tufted needle material. Theyare made onlyin relativelyheavyweight mostly used for carpeting. Conclusion The appearance of a garment is greatlyinfluenced bythe fabric used for construction not all the garments are suitable by some fabrics. To choose a suitablefabricforaspecificendusecallsforbasicknowledgeinfabricconstruction and types offabrics available inthe market. Short Answer Type Questions 1. What is plain weave? 2. What are the types ofweaves? 3. What is knitting? 4. What are purlfabrics? 5. What is weft knitting? 6. What is warp knitting? 7. What are non woven fabrics? 8. What is jersey knit? 9. What are tufted fabrics? Long Answer Type Questions 1. Write about classification ofknit fabrics? 2. How do you identifywarp knit fabrics? 3. Write about needle punched non woven? 4. Write about (a) felt fabrics (b) Lace fabrics.
  • 71. Paper - II Textile Science 147 I. Test yourunderstandings State whether the following statements are true or false 1. Interlacing ofwarp and filling threads is called weaving. (T/f). 2. The simplest weave is a twillweave. (T/f). 3. The knit characteristics are bulky, looselyknitted, rib pearltricot. (T/f). 4.Anyfabric produced on a circular knitting machine is called a circular knit. (T/f). II. Test yourunderstandings State whether the following statements are true or false 1. Nonwoven fabrics are made byweaving. (T/f). 2. Needlepunched nonwovens are made bythe methods that involves the enlargement offabricsto hold themtogether.(t/f). 3. Thepressure ofair causesmechanicalbinding is spunlaced fabrics.(t/f). 4. Fusible nonwoven’s are made fromthermo plastic fibers.(t/f). 5. Felt fabricshave highdrapability.(t/f). Answers forTest your understanding - I 1. True 2. False. (plain weaves). 3. True. 4. True. Answers for test your understanding - II 1. False 2. True 3. False (frictionofwater jets) 4. True 5. False
  • 72. Commercial GarmentTechnology148 Structure 7.0Introduction 7.1 Parts ofloom 7.2 Characteristics ofWoven fabrics 7.3 Weaves Learning Objectives After studyingthis unit, you willbe able to • List out theparts ofthe loom • Understand the various steps inweaving • Know about variations ofthe plainweaves • Types ofweaves • understand the twillweave and satinweave • List out the examples offabrics for the weaves • Know about woven fabrics. Looms 7UNIT
  • 73. Paper - II Textile Science 149 Unit Preview Thisunitgivestheinformationregardingtheweaving process, andthesteps inweiving. i.e. different kinds ofweaves. It explains indetailabout plainweaves and its variations, twillweave and its variation, satinweaveand its variations. 7.0 Introduction The principles of weaving are known very clearlyperhaps a long ago as 400BC ourancestorsknewhow to make baskets and matsbyinterlacing twigs., reeds, and grasses. Later theylearnt how to twist together short fibers, suchas wool and cotton, to form yarn and to weave the yarn in to cloth on a loom, primitive looms were built around a convenient horizontaltree-branch, over whichthe warpthreads were tied. The lower ends ofthethreads were fastened to tietheminposition. Woven fabrics aremade fromtwo ormore sets ofyarns interlacedat right angles to each other the lengthwise yarns are called warp or ends and the crosswise yarnsare called weft or filling or picks. Neat firmedges are formed on bothsides along the lengthofthe fabric whenfilling yarn turns at the edges during weaving. Theyare commonlyreferred to a “selvedges”. Weaving is done ona machine called loom. The wayfilling yarninterlaces withthewarpyarns produces designs inwovenfabrics. Weaving isthemode of interlacement offillingwithwarp. Allwoven fabricsare based onthree types ofweaves whichare termed as basic weaves. The three basic weaves are plain, twilland satin. Most of the other weave are variations or combinations ofthese three weaves. 7.1 Parts of the Loom Fig. 7.1 Structure of the loom and its parts 1 4 5 2 3 67 11 15 8 12 16 9 13 10 14
  • 74. Commercial GarmentTechnology150 1. Warp yarn 2. Warp beam 3. Harness 4. Batten 5. Reed 6. Selvedge 7. Woven cloth 8. Cloth beam. Warp Beam Located at theback ofthe loomonwhichwith the warp yarns are wound. It is acylinder on whichthewarp threads are inparallellines. Theyarns pass to the front ofthe loomwhere theyare attached to cloth roll. Harness This is the frame consisting ofa number ofwires knownas heddles. Each heddle consists an eye through which one or more warp yarns passes. The harnessistheimportant partoftheloomasit hasupwardordownwardmovement of warp yarn, ensures the correct running of the weft yarn over or below the warp yarn to produce the designed pattern in the cloth. Harness contains a number heddles. Fig. 7.2 Harness Heddle It is awere witha holeinthe center throughthe warp yarngoes. There are as manyheddlesas there are warpyarns inthe cloth. Allthe heddles are held in two or more harnesses the warp is raised and lowered by a harness-haddle arrangement. When the harness is raised shed is formed through which the filling yarncanbe inserted. 9. Fell or edge ofthe cloth. 10. Shed. 11. Weft. 12. Shuttle. 13. Bobbin. 14. Dent. 15. Heddle. 16. Heddle eye.
  • 75. Paper - II Textile Science 151 Fig. 7.3AHeedle The Weaving Process Thefirst stepinweaving is tostretchthewarporlongitudinalyarns. ,which must be verystrong. The weft, woof or filling crosses the warp, binding the warp threads at either side formtheselvage. The three essentialsteps after the warp is stretched are shedding or raising every alternate warp yarn or set of yarns to receivetheweft, picking orinserting the weft andbattening or pressing home the weft to make the fabrics compact. In most primitive weaving these operations were performed by the hands alone as in making rush mats and baskets Gradually, frames for holding thewarp evenlystretched anddevices for throwing the weft came into use. Shuttle This holdsthefillingortheweftyarnand ispassedbackwards and forwards across loom. Fig. 7.4AShuttle Reed or Batten It isa frame which is located directlyin front ofthe harness. Fig. 7.5AReed
  • 76. Commercial GarmentTechnology152 This frame pushes forward each time the shuttle passes in between the warp yarns and presses back the filling thread in position. Cloth Beam It islocated inthe front ofthe loomnearest to the weaver onthe which the woven clothis wound. Step in Weaving 1. Shedding : Raising one or more harness to separate the warp yarns and formationa shed. 2. Picking : Passingthe shuttle through theshed to insert thefilling yarn. 3. Beatingup : Pushing thefillingyarninto placeintheclothwiththe reed. 4. Let off : Warp yarns are released fromthe warp beamso that weaving maybe carried out. 5. Take up : Winding offinished cloth on the cloth beam 7.2 Characteristics of Woven Fabrics Selvedges: In most of the materials the edges, which are known as selvedges, aremade withheavierandmorecloselyplacedwarpyarns. Selvedges is generally¼ to ¾ inches wide on fabrics. The yarns are usuallythe same as those in the rest ofthe fabricexcept that they are made firmer and stronger byincreasing the size or count of the way yarns in selvedge. Fused selvedges are found on fabrics made from the heat sensitive fibre. The applicationofheat melts and thenseals the fibre together at the edges. Count of the Cloth : Count is the technical term used to indicate the number of warp and the weft (the filling yarn or picks) in one square inch of fabric as it comes from the loom. If warps are 90 and the wefts are 80, the count writtenas90 x80 anda fabric in whichthe warp yarns andweft yarns are more in number it is called as high count fabric. Averylow count fabric is one inwhichthewarp and the weft yarns number 28 and 24respectivelyexample in surgicalgauze. The exact numberofwarp andtheweft yarns inasquare inchof fabric canbe counted with the helpofan ordinarymagnifying glassheld over a tightlystretched piece ofcloth. But allthis is not necessaryifthe aimis onlyto judge whether the cloth is of a high or low count. If the weave is a veryclose one and tiny spaces are visible between the weave and the cloth it could be a closelywoven fabric.
  • 77. Paper - II Textile Science 153 If the fabric is held against the light, the closeness of the weave or its porositycan beeasilyobserved. Threadcount is an indicationofthe closeness ofweaveandcanbeused bytheconsumerinjudgingquality, ravelling, durability and potentialshrinkage. Fabrics with close weavegenerallyshrink less. Balance of cloth Low count fabrics are woven with a fewer interlacing per square inch to make the fabric light-weight. Due to this a porous structure is formed. The balance offabric is determined bythe proportion ofwarpyarnto weft yarns. If the number of warp and weft yarns is nearly the same in a square inch the fabrics havea good balance fora example, ginghamwitha count of96x88 and guage withthe count of28x24 are materialwitha goodbalancebut the shirting with 100 warps and 50 picks has a poor balance.Afabric with a poor balance whenheldagainst thelight willshow moreyarnsrunninginonewaythatislength wise only. Such a fabric is not good as it does not stand hard, wear and many washings. Thestrengthofthefabriccanbetestedbytightlyholdingandstretching a pieceoffabric, and rubbingit repeatedlyusing thumbs. Ifanyyarnslips out its place and the tinyspaces betweenthe weave gets enlarged, it indicates that the fabric is not as strong as it looks. Yarns Warp and filling have different characteristics and the fabric performs differentlyinthewarpand filling direction. Stronger yarns are usedinthewarp- wise directionas theyundergo moretension and friction thanweft yarns. Most fabrics stretchedless inthe warpdirection. Warp yarnslie straight in the fabric because ofloomtension. Theyshow less crimp. Warp yarns tend to be stronger with higher twist. Decorative or specialfunction yarns, yarns with slack twist, yarnswithlittle twist are usuallythe filling yarns. Grain The grain indicate the direction of the warp or weft yarns. Length wise grainis apositionalongthe warpyarnsand paralleltoselvedges crosswise grain is alongthe filling yarn. Weaves Weaves arenamedaccording to thesystemordesignfollowedininterlacing warp and weft yarns. The basic weave used in fabric construction are: Plain weave, Twillweave and Satin weave. These are the foundation weaves and formthe basis ofallother types ofweaves.
  • 78. Commercial GarmentTechnology154 Plain weave Plainweave is the simplest ofallthe weaves.About seventypercent ofthe woven fabrics available in the market today are woven in plain weave or it variations. It is formed byinterlacing warp and fillingyarns ina patternofover one and under one. (fig-1) In the first row the filling yarn moves over the first warp yarnand under the second, over the third, under the fourth and so on. In the second row, the filling yarn moves under the first warp yarn and over the second warp yarn. These two rows are repeated to get the pattern of plain weave. Plain weave fabrics have no right or wrong side. Plainweave provides a wide scope forintroducing variations inthefabrics byuse ofyarns ofdifferent colours, different textured yarnandalso byuse ofthick and thinyarns. Fabrics can be produced in large variety, withdifferent degrees of yarntwist and with different degreesoftensions in the loom. Fabrics made bytightlytwisted warp and loosely twisted weft make it easy for a napping finish to be given to it. Example: flannelettes,stripedmaterial,plaidsaremadebyusingdifferent coloured yarns at intervals eg. ginghams. Plainweaveis made interesting byprinting and embossing. Plainweaving also allows the use ofmanydifferent finishing processes to produce varieties and different styles offabrics. Plain weave is used in the construction ofthe fabrics fromalmost allthe textile yarns cheapest to produce. It is the most serviceable ofall weaves as fabrics,with this weave are easy to wash, dry clean, wear well and are comparativelyinexpensive. Fig. 7.6 Structure of Plain weave
  • 79. Paper - II Textile Science 155 Plain weave fabrics Cotton : Calico, cambric, canvas, cheese cloth, chintz, cotton, crepe, flannelette, gingham, long cloth, muslin, organdy, seersucker and voile. Linen : Cambric, dress linen, hand kerchieflinen and toweling Wool : Crepe, Flannel Silk : Chiffon, crepe de chine, crepe georgette, taffeta and voile. Rayon : Chiffon, crepe, georgette, seersucker, organdy, taffeta and voile. Plain Weave Variation Rib weave : It isthe variationoftheplain weave. Inthisheavier yarns are used is the warp thanthoseis the weft andthis produces a ribbedeffect. Some times the order is reversed and the heavier yarn is used in the weft. Eg. Faille grass grain, broad cloth, poplinare someofthe examples. Fig. 7.7 (a) RibWeave (b)RibWeave
  • 80. Commercial GarmentTechnology156 Basket Weaves Basket weaves is a balanced weave. In this two or more yarns in both warp and filling are treated as one and interlaced as in plainweave. The fabric with basket weave have. Flenth and ifthe count is not very high the fabric is evenporousand pliable. However, fabricswitharrangements such as3x3, 4x4, 6x6 snageasily. This weave isused inmaterialforsports coats and suits. This is a comparitivelyloose weave and thereforethe fabrics are morelikelyto shrink. Fig. 7.8 BasketWeave Twill weave This weave forms Wales diagonally across the face of the cloth. This is brought about bythe interlacing ofwarpand filling yarns witha progression of one at thepoint ofinterlacing
  • 81. Paper - II Textile Science 157 Example : If the first filling covers warp yarns 2,3,4,5,6,8 and 9 goes under 1,4,7, then the second filling will go over 1,3,4,6,7,9 and 10 and then goes under 2,5,8, and so on. The simplest formofthe twillweaves is made by throwingthe fillingyarnover a two warp yarns, thenunder one, over two under one and so on. At least three harnesses should beused inthe loomto weave the fabric. The direction ofdiagonalinthe weave can be created fromright upper hand orleft upper hand called as right hand left hand twills respectively. Avariationofthisweave is “Herringbone” structure. Inthisthe diagonal directionis purposefullyreversed creating a designresemblingthe backbone of fish. Thus it is termed as herringbone. Another variation is made from a diamond pattern. Variations are also introduced byusing yarns ofdifferent sizes, qualities and colours. Twillweave has fewer point ofinterlacing than plainweave. So it permitscloser packing of warp yarns to produce heavier fabrics whichresults in longer wear. Twill weave produces strong material because ofthe tightlyyarns which areused tobring out the diagonaleffect andthecompactnessofits construction. Twill weave fabricsare mostlyexpensive becauseoftheirelaborate construction on but theyare strong, standhard and long wear. This weave is generallyused in wool and cotton fabrics where durabilityis a prime necessity. Twillweave fabrics do not show dirt ordust as muchas the fabric woveninplain weaves do and are therefore more suitable for dresses, men’s shirts and suits and children garments. The side onwhichdiagonaleffect ismore prominent is the right side ofthe cloth. But when twill-weave fabrics are finished by“napping”the napped side is theright side. Fig. 7.9 Twill weave
  • 82. Commercial GarmentTechnology158 TwillWeave On Fabrics Cotton : Denimdrill, gabardine, jean, khaki, serge. Linen : Table linen, towels, drills, and ticking Wool : Broadcloth, cash mere flannelgabardine, tweed, serge, worsted Silk : Twill, serge. Satin Weave Satin weave fabrics are characterized bylustre and smooth surface. They are similar to twillfabrics except that the floats are long and diagonallines are not visible. Satin weave is one in which each warp yarn floats over four or more number of filling yarns and go under one fifth yarn with a progression of interlacement bymorethanone, thusavoidingtheformationofthe diagonallines whichwillinterferewiththe lustre ofthe fabrics. Thelongerfloats permit closer package ofyarns and thus satinfabrics normallycontainmore number ofyarns than plainweave fabrics. Satin fabrics have a right and wrong side. A high count of yarns in the fabric provides strength, durability, bodyand firmness. Their smooth surface provide more lustre. Low count fabrics are not durable and tendto ravelmore. Fig. 7.10 Four float satin weave Fig. 7.11 Seven float satin weave Sateen Weave A variation ofsatin weave is sateenweave. It is characterised byhaving filling yarn floats on the surface. These are less lustrous and less durable as filling yarns are generallyweaker comparedto warp yarns.
  • 83. Paper - II Textile Science 159 Fabrics inSatin weave: Washable satin, satin crepe, slipper satin etc. Fig. 7.12 Sateen Weave Suitability of Weaves Various End Uses When suitabilityis a major factor, the consumer should carefullyconsider the enduse or the purposefor which the fabricis to be used Plainweave fabrics are firm and considered to be more serviceable as they are laundered or dry cleaned, comfortable to wear and convenient. Theyare versatile, ranging from light weight fabricsto heavyweight fabrics. Light weight or sheer fabrics are suitable mainly for children’s dresses, blouses, summer shirts, sarees and glass curtains, mediumweight fabrics are mainlyused for shirt, women dresses, pyjamas and aprons. Heavyfabrics are used forupholsterymaterials, suiting etc..Allplainweave fabricsare easilysew able and areexcellent for creating styles throughmix and match. Ribbed fabrics aresuitable mainlyfor furnishings andbasket weave fabrics are suitable forshirting’s and furnishings. Twill weave fabrics have interesting surface due to diagonallines on the surface and are also durable. Theydo not show much soiland required only little ironing. So theyare suitablefor work and sportsclothes.(Theyare mainly used for menswear even in wool.).They keep up the shape well and so are excellent for suitings. Satin fabrics are not suitable for daily wear due to the presence oflong floats. Theycanbe selectedfor occasionalevening wearforwomenappearance and style governthe satin, hence theyare more expensive. Theyare considered to be best lining fabrics for coatsand shirts because theyslide easilyover other fabrics.
  • 84. Commercial GarmentTechnology160 Conclusion Abriefstudyofweavesenableagarment designertochoose suitablewoven fabrics for different styles. Plain twill and satinare the weaver that form the basis structure in allfabrics plainweave being simple and inexpensive forms a good background for printing. Twillweave produces durable fabrics. Satin weave produce smooth, lustrous fabrics that are suitable for linings I. Test your Understanding State whether the following statements areTRUE / FALSE 1. Twillweave forms waves diagonallyacross the faceofcloth (T/F) 2. Examples oftwillweave are Gabardine, Jean (T/F) 3. Satin fabric isnot lustrous and not insmooth surface (T/F) 4. Sateen weave have the filling yarnfloats onthe surface (T/F) 5. Sateen fabrics are suitable for dailywear (T/F) Multiple Choice Pick upthe correct answer fromthe following questions: 1. One ofthe steps in weaving are a. shedding b. warp c. weft d. grain. 2. Edges are known as a. count b. balance of cloth c. yarn d. selvedge 3. Basket weave is a a. Balanced weave b. rib weave c. satin weave d. twill weave. 4. Satin weave fabrics are characterized by a. rough b. float c. yarn d. luster 5. Twillweave fabrics are mainlyused for a. children’s wear b. ladies wear c. men’s wear d. instant
  • 85. Paper - II Textile Science 161 Short Answer Type Questions 1. List out the basic weaves with2 examples each? 2. what are the variations ofplainweave? 3. which is the strongest ofallbasic weaves? Why? 4. List out the characteristics ofsatin fabrics? 5. write about basket weave? Long Answer Type Questions 1. With neat labeled diagramdraw the parts ofloom? 2. what are the steps inweaving? 3. what are the characteristics ofwoven fabrics? 4. what is a weave? Describe plain weave with neat diagram? 5. Describe twillweaveand its variations? 6. Describe satinweave and its variations? Answers or test your understanding - I 1. True 2. True 3. False- lusterand smooth surface 4. True 5. False- not suitable Answers for Multiple choice questions 1. a. shedding 2. b. selvedge 3. a. balanced weave. 4. d. luster 5. c. men’s wear
  • 86. Commercial GarmentTechnology162 Structure 8.0Introduction 8.1 Classificationsofstains 8.2 Generalrules to be observed inremovalofstains 8.3 Methods and reagents required for theremovalofstains Learning Objectives After studying this unit, the student willbe able to • Explainthedefinitionofsatin. • List out thevarious types ofstains • Understand the generalrules to be observed inremovalofstains. • Know about commonstains and the reagents required for removalof stains onvarious fabrics. Unit Preview This unit helps inunderstanding thestains, the generalrulesto be followed forremovingthestains, reagentswhicharerequiredtoremovestainsanddifferent methods for removingthestains fromthefabrics. Stains 8UNIT
  • 87. Paper - II Textile Science 163 8.0 Introduction Stain is spot or mark of discolorations on fabrics by the contact and absorptionofforeignsubstances. The need to clean and care for a household is always with us. For a successfulstainremovalprompt action is important as a quick dealwith a stain is more likelyto remove it simply.Withmost stains, trycoldwater first, flushing the water throughthe materialifpossible. Make sure that thecleaners used are known and awareness ofthere is also known. But as a generalrule, ifone can safelyeat it.Forexamplelemonjuiceandbicarbonateofsodait isenvironmentally kind as a cleaner. Stainremovaland spotting is askillwhichcalls forexperienceanddemands specialattention. The essentialfactors to be kept inmindwhile removing stains are: (1) The compositionand colour ofthe fabric. (2) Thenature and age ofthe stain. The stainremovalis amajorstore filled withdifferent formulae designed to remove ourstains indailylife. It is agreatasset to thecleaningsolutions tackling everything to wipe out dailystains. These stains with theirrespected removing reagentsarespecifiedinthegivenchapter.Thusthestudentscanobtainmaximum knowledge regarding the stains and their methods ofremovals. 8.1 Classification of Stains Broadlyspeaking stains are divided into (a)Animal (b)Vegetable (c) Greece (d) Dye (e) Mineral Animal stains are those caused by blood, egg, milk, meat and juice. As these containproteinmatter heat mustbe avoided inremovingthem. Otherwise the proteinmatter gets fixed to the stain. Vegetable stainsinclude those caused bytea, cocoa, coffee, fruit and wine. These areacidic and therefore requirealkaline reagents to remove these stains.
  • 88. Commercial GarmentTechnology164 Greese stainsmaybe just greese spots or some coloring matter fixed with greese. Theseinclude butter curry, oilpaint, varnishand tarstains. Inremoving these stains some greese or an absorbent is first used to dissolve or absorb grease before the removal ofthe coloring matter. Asolvent soap is also very effective for removing these stains fromwashable fabrics. Dye satins maybe acidic and so that the nature ofthe stain is ascertained before a specific removing reagent is used. Mineralstains such as ironmould, black ink and certain medicine stains are compoundsofa metalanddye. These are first treated byacid reagent to act on the metaland thenbyanalkaline solutionto neutralize theacid reagent and act onthe dye. 8.2 General rules to be observed in removal of the stains 1.Allthe stains are easilyremoved when fresh. 2. Ifthe nature ofthe stain is unknown it should be treated bythe least harmfulmethodsfirst going one processto the next untilaneffective agent is reached. Theyareas follows: (a) Soak in cold water. (b) Soak in warm water (c) Bleachinopen air, iftime permits. (d)Treat withan alkaline solution (e) Treat withanacid solution. (f)Treat withoxidizing bleach. If the above methods fail (g)Treat withreducing bleach. (h) Inthe event ofstainpersisting whichis unlikelytreatment with alkaline solutionor with reducing bleachcan be repeated. (i) Known stainsshould be treated withtheir specific reagents. (j) Bleaching treatmentsshould be tried asthe last resort astheseshould be takenfromseveralapplications ofweaksolutions rather thantheuse of strongsolutioninone application.
  • 89. Paper - II Textile Science 165 (k) Reagents maybe spread onto cotton and linenfabrics and boiling water maybe poured throughthe fabric. 8.4 Common stains (a) Ball pen Reagents required: Methylated spirit Method: Rub lightlywith methylated spirit, swabwith methylated spirit using a padofblotting paper below. Same methodfor acotton,linen, silk, wool, and synthetics fabrics. (b) Boot polish Reagents required : Methlated spirit Method: Boot polishismade bydissolvingcertaincolors inwax. The wax isremovedbymeans ofsolvents.Thiswillalso removethe color. Ifthecolor still remains treatment withmethylated spiritwillcompletelyremovethe stain. (c) Blood Reagents required: Cold salt water, hydrogen peroxide. Method: A fresh blood stain on clothing can be rinsed out in cold salt water. Ifthe satin is dried bleach with a drop ofhydrogen peroxide. (d) Gumand glue stains Reagents required:Glycerinoraceticacidormethylated spirit orhot water. Method:Treat withhot water tosoftenand dissolve thestain. The addition of a few drops of glycerine will assist in dissolving the stains in some cases otherwise few drops ofacetic acid also willhelp. (e) Stained brass Reagents required:Lemonsprinkled withsalt. olive oil. Method : Agreener wayis to rubwitha piece oflemonsprinkled withsalt or the other is rinses withdrythen rubs withthe olive oil. (f) Greese or oil Reagents required: Greese solvent, Frenchchalk or fullers earthpowder. Method: Ifthe satin is fresh washwith hot water and soap and ifit is dry treat withgreesesolvent and washwithhot water and soap forthe white cotton and linen.
  • 90. Commercial GarmentTechnology166 French and fullers earth are sprinkled on the stains to absorb the greese then washit withwater. Forunwashables Treat withgreese absorbents spread Frenchchalk or alkalies earthon the stainleave it for one hour brushoffthe powder. Butter Reagents required : Absorbent paper Method : Scrape offas much as one can. Iron with warmiron between layers ofabsorbent papers. Lipstick Reagents required: Bleaching powder, methylated spirit kerosene or turpentine. Method : Steep inmethlated spirit and washwithsolvent soap. Moisture andsoftenbyworkingwithglycerine. Leaveit for short time andthenwashwith soap or surf. For synthetics fabrics steep in kerosene or turpentine wash with soap and hot water. Better trycold water first and thenwash in warmto soapy hot water. Candle wax Reagents requires:Blottingpaper Method : Put inplastic bag inthefreezer for sometime scrap it or sodified it. Thenplacefabric betweensheets ofblotting paper and ironwitha warmiron. Marking ink Reagentsrequired:Iodinesolution, sodiumthiosulphate, salt. Tomato, sour milk or curd, salt and lie juice. Methods :Rubthestainwithcut tomatoand wash. Steepiniodine solution andthenbysteeping insodiumthiosulphate solutionandwash.Bleachaccording to the fabric. Rub salt and wash repeat tillstainis removed. Mildew Reagents required : Javelle water, potassiumpermanganate, oxalic acid. Mildew is formed bythe growthoffungus on the damped fabrics Method: (a)Bleachbysunlight
  • 91. Paper - II Textile Science 167 (b) BleachbyJavelle water. (c) Bleachbypotassiumpermanganate. (d) Bleachwithhydrogenperoxide. Potassium permanganate for cotton and linen: Dissolve one ounce of permanganate crystals inone gallon ofwater. Mildew onsilkand cotton:Takehalfofpermanganate crystalsinngallon of water. Steep materials for 5 minutes till it becomes dark brown and then remove the brownstainbyapplying anyone ofthe followingdilute solution of sulphuric acidoroxalic acid oracidifiedhydrogenperoxide. Rinsethoroughlyin three changes ofwater and washaccording to the typeofmaterial. Mildewoncotton:Applysoaplather onthestains andcoveritwithFrench chalk andplace it inthesunto bleach. Repeat the process tillthe satinis almost removed thentreat iot with lime juice wash withjavelle water. Preparation ofjavelle water or hydro chlorite. This can be prepared and stored Washing soda = 500grams Boling water= 1 liter Chloride oflime = 250 grams Cold water = 2 liters. Method: Make a solution ofwashingsoda and boiling watermixchloride of lime with cold water stand the mixture for some time so as to settle down decant a clearliquid and add it to washing soda solution. This willgive sodium hydrochloride and calciumcarbonate willprecipitate.Allowthe precipitate to settle andthenstainofftheclear liquid. This must be stored incoloredbottles as it deterioratesinthe light. Some procedurefor colored cotton, silk, wooland synthetic. Jams and stains Reagents required:Boraxsolution. Method:Removejamstainsfromwashableclothesbysoakinginasolution ofboraxand water then washas usual. Tar Reagents required: Oil, greese solvent, kerosene
  • 92. Commercial GarmentTechnology168 Method : Spread a little on the stain, let it dry and repeat untilthe mark disappears. 1. Ifnecessaryscrap first. 2. Rubwithoilor greaseusing a cleanclothand working fromedgeofthe stain to the centre. 3. Treat withgrease solvent. 4. Treat with kerosene. Chewinggum Reagents required : Ice pack Method : Put the garment in aplastic bag in thefreezer for a wholeor put a icepack inthe gum. Crack offthe solidpieces. Sponge the remainderwithdry cleaningfluid. Iron stains Reagents required:Toothpaste Method : To cleanthe outside ofyours ironuse tooth paste as irontools. Tea and coffee Reagents required: Borax, washing soda, javelle water. Method : For freshstain(cottonand linen): Pour boilingwater throughthe stainfor drystain: 1. Steep inboilingwatercontainingsodaorboraxorbothorapplyglycerine and steep inhot water soda solution. 2. Bleachwith javelle water. 3. Bleach withsodiumper borate. For silkand wool fabrics For stain: Steep in warmwater, repeat tillsatinis removed. Dry stain 1.Applyglycerine and steep inwarmborax or weak ammonia solution. 2. Use hydrogen peroxide bleach. 3. Usehydrosulphite bleach.
  • 93. Paper - II Textile Science 169 Chocolate Reagents required :Boiling water, detergents. Method : On clothing scrape off the solid chocolate with a blunt knife. Pour boiling waterfroma height oruse detergent and work fromback ofstain. Hair dye Reagents required: Cold water, liquiddetergent ammonia. Method : Rinse fabric immediately with cold water then wash in warm water withliquiddetergent and ammonia. Curry Reagents required :Methylated spirit, diluted ammoniaor white spirit. Method : Soak stain with methylated spirit, diluted ammonia or white spirit Ointment stain Reagents required: Drycleaning solution, Liquid detergent. Method :Trydrycleaning solution, thenrinse incold waterthen work in liquid detergent and rinse again. Pan Reagentsrequired: Pottassiumpermanganate solution, sodiumper borate, hydrogen peroxide. Method: Treat withpotassiumpermanganate Treat withsodiumperborate. Treat withhydrogenperoxide and thenwashwith soap water. Medicine Reagents required :Oxalic acid, methylated alcohol. Method: 1. Steep in warm water. 2. Steep in oxalic acid. 3. Steepin methylated alcoholorsurgicalspirit. Egg Reagents required : Soap and warmwater.
  • 94. Commercial GarmentTechnology170 Method : Wash in cold water and then in warm water and soap. Apply salt and pour warmwater. Rust Reagents required : Oxalic acid, dilute boraxsolution, salt and lemon. Method :1. Steep in oxalic acid and thenrinse with dilute borax solution. 2. Steepinsolution ofsalt and lemon. Scorch Reagents required: Dryborax, Wet muslinammonia. Method : Bleaching inthe sunlight is best.Applt soap lather to stain and place it in the sun. Keep the stain with moisture and while it is inthe sun. Rubwithdryboraxand wet muslin over stain. Steep indilute ammonia place the stain inthe sunfor bleaching. Nail polish Reagents required:Acetme Method : Applyto the stained area witha cotton woolpad this must not be used onacetate rayon fabric.Ice cream: Reagents required: Petrolor carbon tetrachloride, borax. Method : (a) Wash in cold water and soap. (b) Steep inwarmboraxsolution. (c) Sponge withpetrolor carbontetrachloride. Perfume Reagents required: Ethylalchohol, Hydrogenperoxide. Method: (a) Treat withethylalchohol. (b) Bleachwith hydrogenperoxide. Turmeric Reagents required: Hydrogenperoxide, sun and grass. Method : Soak inhot soap water and dry in sun or the grass.
  • 95. Paper - II Textile Science 171 Apply a few drops of hydrogen peroxide leave for few minutes, rinse thoroughlyand dryin the sun. Conclusion The processofremoving eachsatinwithreagents suitable to the fabrics is important. Thereagentsshouldnot damagethe fabric. Hence correct procedure should be followed to remove the satin from the fabric and at the same time retainingftheoriginaltexture offabric. Stain 1.Blood 2. Butter 3. Curry Condition Fresh Dry fresh fresh fresh Freshdry Synthetic fibre Washincold water Coverthesatinwith French chalk place the stained portion between clean blotting paper. 1. Wash with soap and water. 2. Bleach with sodiumperborate. White cotton and linen Soak in cold water and wash in dilute ammonia. Soak in cold water and salt Wash with warm soapysolution 1. Wash with soap and water. 2. Bleachinsunlight and air. 3. Bleach with javelle water. Silk Sponge with cold water. Same as white cotton for unwashable fabrics apply starch paste. 1.Same as cotton use French and clean with blotting paper. Iron by hot iron. 2. Cover by solvent soap. 1. Treat with solvent soap. 2. Treat with p o t a s s iu m permanganate and ammonia.
  • 96. Commercial GarmentTechnology172 4. Dye 5. Egg 6.Turmeric (Haldi) 7. Ice cream 8. Ink Fresh Fresh dry Fresh Dry Fresh Fresh Fresh 1. Steep in water 2. Wash with soap and water. 3. Treat with alcohol and dilute acid or bleaching powder. 1. Wash in cold water and then in warm water and soap. 2. Apply soap and thenwarmwater. 1. Same as curry stain 1. Wash in cold water and soap. 2. Steep in warm borax 1. Apply salt and lime juiceand leave for some time 2. Soak in sour milk and curd. 1. Wash with water and soap. 2. Treat with diluted bleaching powder. Same as cotton. Steep in salt solution. Same as curry stain Same as cotton. Same as silk or wool. 1. Treat with alcoholor ammonia. 2. Bleach with hydrogen peroxide. Same as cotton Steep in salt solution Same as curry stain 1. Wash with cold water and soap. 2. Add ammoniato soap. Treat with sour milk or curd for white cotton
  • 97. Paper - II Textile Science 173 9. Ball point ink 10. Iron rust 11. Lip stick 12. Medic- ine 13. Mildew Fresh freshand dry Fresh and dry Fresh and dry Fresh and dry Swab with methylated spirit usingblotting paper. 1. Steep in oxalic acid and then rinse inborax 2. Steep in solutionofsalts and lemon. 1. Steep in methylated spirit washwith solvent soap. 2. Use glycerine and rinse 1. Steep in warm water. 2. Steep in oxalic acids and wash withborax. 3. Steep in methylatedalcohol orsurgicalspirit. 1. Bleach with javelle water. 2. Apply soap lather and cover with Frenchchalk and place in sun to bleach Same as cotton Same as cotton Same as cotton. Same as cotton Bleachwith hydrogenperoxide Same as cotton Same as cotton Same as cotton Same as cotton Bleachwith hydrogen peroxide
  • 98. Commercial GarmentTechnology174 14. Nail and varnish 15. Oil and paint 16. Per- fume 17. Scorch 18. Shoe polish 19. Tea and coffee Dry Dry Fresh and dry Applyacetate to stained area with a cotton pad. 1. Steep in turpentine wash withsolvent soap. 2. Steep in alcohol and theninsolvent 1. Treat with ethyl alcohol. 2. Bleach with hydrogenperoxide 1. Rubwith borax andwet muslin over the stain. 2. Steep in dilute ammonia place the staininsunfor bleaching. 1. Scrape ofthe stain ifdryapply little grease wash with soap and water. 2. Steep in turpentine wash withsolvent. (a) Pourboiling water 1. Spread borax and pourboiling water. 2. Keep in glycerin untilstainis removed. As cotton For rayonalcohol is not used. Bleachwith sodiumperborate. Same as cotton. Steep in kerosene and turpentine and washwithsolvent Same as silk. As cotton Same as cotton Same as cotton Same as cotton Steep with alcoholwash withsolvent Steep with boraxsolution Treat with hydrogen peroxide.
  • 99. Paper - II Textile Science 175 Test your understandings State whetherthe following statement istrue or false 1. Stainis a spot left on fabrics (t/f). 2. Stains are divided into 7 types (t/f). 3. Examples ofanimalstains are blood and egg (t/f). 4. Examples ofvegetables stains are milk and meat (t/f). 5.Allstain are easilyremovedwhen dry(t/f). 6. Ballpens can be removed bymethylated spirit (t/f). 7. Boot polishstain can be removed bywater (t/f). 8. Marking ink canbe removed byiodine solution (t/f). 9. Tar can be removed bygrease solvent (t/f). 10. Tea and coffee can be removed by borax (t/f). Short Answer Type Questions 1. What is a stain? 2. What reagents are required for removing a) Ballpenb) Tar 3. How do you remove lipstick stainfromcottonfabrics? 4. Write thesteps involved inremovingthe mildew stains? Long Answer Type Questions 1. What is a stain?Explainthe classification ofstains withexamples? 2. What are the generalrules to be observed inremovalofstains? 3. List out anyfour common stains andtheir removing agents? Answers forTest yourunderstanding 1. True 2. False-5 types 3. True 4. False-coffee, tea, cocoa, etc 5. False- when fresh or wet 6. True’ 7. False-methylated spirit 8. True 9. True 10. True
  • 100. Commercial GarmentTechnology176 Structure Finishes 9UNIT 9.0Introduction 9.1 Calandering 9.2 Singeing 9.3Tentering 9.4 Mercirizing 9.5 Bleaching Learning Objectives After studying this unit, the student willbe able to • Explainthemeaning offinishes. • Identifythe need whyfinishing process is required. • List the variousfinishing process for fabrics. • Understand the effect ofcalendaring infabrics. • Understand theprocedure ofsingeing. • Importance oftenteringis required for fabric. • Reasonfor silkylustre and beautifulsheenis seen incotton fabrics. • Importance ofbleaching and its use.
  • 101. Paper - II Textile Science 177 • Distinguishingthebleachingagents. Unit Preview This unit helpsinunderstanding the different fabricfinishing process. The finsihing processesincludes Calendring,, Signeing, Tentering, Mercerising and Bleaching. 9.0 Introduction Finish is defined as anything that is done to fibre, yarnor fabric to change its appearance. The finish oftendetermines the fabric care required. Finishing alters thesurface ofafabric and therefore itslookand feel. Ffabricsor garments generallyhave to be finished to make the materialpresentable and attractive. It is often the finish which increases the sales value ofthe textile goods finish is usuallyapplied to fabrics. As yarn and fabrics comes fromthe spinner weaver and knitter they are often inunfinished condition. The materialmaybe harsh to handle and contain impuritieseither thoseadded to facilitatethemanufacturingprocessorimpurities which are naturalto fabrics. The materialmayalso be soiled andhave oilstains. In fact, materialsfresh fromtheir manufacture are referred to as beingin a grey orbrownstate. The finishingprocessesare requiredmake thematerialsattractive theyalso improve their serviceability. Classification of finishes Finishes are classified on several basis the newly constructed fabrics as theycome out of the loomare called greygoods. This does not mean that the colors ofthe fabrics is grey, but it simplymeans that anyunfinished fabric must pass throughvarious finishing process to make themsuitable for end use. The aims ofthefinishing process are: 1. To makethe materialattractive. 2. To improvesuitabilityand utility. 3. To produce variety. 4. To give weight. Finishes are classifiedin to two types 1. Mechanical 2. Chemical
  • 102. Commercial GarmentTechnology178 Finishes Mechanical Chemical (use of mechanical methods) (use of chemical) Finishes Permanent Temporary Renewable (Eg. Parchmentization) (Moire Calendering) (Stiffening) Dyeing is sometimes considered part of the finishing process. It can be sometimes be carried out at the same time that the fabric is straightened and brought to its desired finish, width and length for other processes, the fabric must be driedfirst and thenlightlydamped for the finalfinishing treatment. The most commonfinishing process are listed below.The list is not a sequence nor allare theprocesses used onallkinds offabrics. Some fabrics go through more thanone process while each fabric is given its owncharacteristic finish. 9.1 Calendaring Calendaring is essentiallyan ironic process. Most fabrics(and yarns too) become stiffboard like when wet and dried under tension. Running the fabric through a calendar removes the stiffness and makes it quite soft.At the same time calendaringflattenstheyarns andmakesit so lustrous. The process consists of applying a lot of pressure bypassing the cloth between cylinders ofheavy weight of compressed cotton and steel. Rayon fabrics are not calendared as heavilyascotton or linen, but silk oftenrequires fairlyheavycalendaring some calendars use waxy calendars substances to give added luster in addition to friction treatment bysteamheated pressure cylinders. Calendaring flattens andclosethe threads ofthefabricto giveit therequired smoothfeelandappearance. The finishdependschieflyonpressure, temperature and moistures. 9.2 Singeing The object ofsingeing is to remove the short fibers fromthe clothcoming off a loom. The cloth is first passed over one or two stream heated copper cylinders to remove moisture and to raise a nap. The projectingfibres are then
  • 103. Paper - II Textile Science 179 singed(burnt) bypassing theclothoverahot plate orthrougha gas flameat high speed, leaving thecloth with a smoothsurface. It is immediatelyput into water to remove anysparks. 9.3 Tentering To bring a fabric to the right width it is passed through a 20-90 feet long tenteringmachine.Theclothiscarriedthroughthemachinebytwomovingchains ofclips or pins one oneach side which grip the selvedge firmly. Tentering is animportant and necessary operation because the fabric has been pulled in length during bleaching, dyeing and drying and is therefore generallynarrower thanthe required finished length. During the operation the clip chaindivergefromthe entryend about one quarter or slightlyless thanthe lengthofthe machine.As theclothis carried forward, grippedoneither sideit is graduallywidened. In order that thestretching maytakes placeeasily, the cloth is slightlydampened or steamed.After stretching it is passed througha hot air chamber to dryand set at this width. Fig. 9.1 Tentering or Straightening of the fabric
  • 104. Commercial GarmentTechnology180 9.4 Mercerising Applying the causticsoda under controlled conditionsgives cottonfabrics a silky luster and beautiful sheen. It also gives the cloth a greater affinity for coloring matters forespeciallydeeper, brighter shades with dye stuff. The clothis impregnated withan18-20% solution ofcaustic soda for one halfoftwo minutes at roomtemperatures. Theclothisstretchedwhilesaturated andthenwashedoutwhileitisstillintension.Thetreatmentproducesapermanent change inthe structure ofthecottonfiber. Types of Calendaring Variations ofcalendaring processinclude thefollowing moireed, embossed and glazedfinishes. Theyare: 1. Moireing : One ofthe most interesting surfaces is the ‘moire’finish.A cloth with a filling wiser rib weave is run between rollers engraved with many lines and thusgivena watered effect. Onacetate clothes. The finishwillremain ingoodconditionafterthefabricsarelaundered. Rayonsaregivenresintreatment to set the design. 2. Embossing : The fabricis passed betweenheated rollersthat imprint or emboss the design on the fabric. This design is less expensive than a woven design. 3. Glazing :After the fabrics are bleached, dyed or printed theymay be given a stiff polished or glazed surface. Starch glue or resin may be used to stiffenthefabric. Thensmoothhot rollers that generatefrictionare applied since the advent ofresins inthe finishingfield permanent finishgaze canbe applied to chintz andother muslins. Finishes that appealto touch: Some finishes improves the softness ofa fabrics. For example softeners’ and hard builders must be used on nearly all durable pressfabrics. Polyethylene emulsions improveabrasionresistance, sew ability, fabrichand. These emulsions haveincreased inuse assofteners since the advent ofdurable press. Other finishesgives weight and bodystillothers gives crispness and stillothers warmth. Napping : The warmth and softness of wool flannel or a brushed wool sweater is due in part to the fuzzy soft surface called nap. It is the process of raising short fibers ofcloth to thesurface bymeans ofrevolving cylinders with metallic points. Cotton and synthetic fabrics of spun yarns maybe napped to resemble woolin texture. Generally yarns used in the fabric should have low twist.
  • 105. Paper - II Textile Science 181 Parchmentizing : These are the permanent finishes on cotton and still remain ofgreat importance. They were discovered by John Mercer in 1844. Thehigherconcentrationofthesulphuricacidproducestheparchmentisingeffects. Parchmentising acid probablygelatinizes the surface ofthe cotton and causes the fibers ofcohere some extent. Burnt out finish : Burnt out finishgives transparent effect possible on blended fabrics onlylooks different fromothers. Formsopaque wovendesigns against a transparent back ground.. Burnt out or etched finish : Etched effects are produced by printing certainsolvents ona fabric make offibers ofdifferent fibergroups. For example polyester, cottonor rayon. One fiberwillbe etched awayleaving it sheer as it in itched rayon silk velvet. This results in producing opaques designs against transparent backgrounds. Thusstiffeningthefabric as distinct fromthe yarns whichare also stiffened. Linen likeeffects are produced, but the acid is rinsedawaythe fabric isdried on the stenter equippedwithjigging motionto breakdowntemporaryadhesions of the warpand weft at points ofintersection. Organdie effects maybe produced inthis way. Alterationsoftheparchmentizing and mercerizing at low temperatures are capable ofgivingspecialtransparent effects knownas swiss finish. Starch less finish:To reducethe use ofstarchfor a crisp finishthat canbe durable for repeatedwashings. Cottons are treated withresins. This starchless finishispermanent and does not dissolves inlaundering. Wash and wear: Permanent starch less finish can be used on curtains, draperies, sheer cottonsfor apparel. It isused onorgandy, lawn, voile and other sheet cottons. Sizing, stiffing and starching: To increase the weight, bodycrispiness, stiffness and luster cotton and polyester blends are stiffed. Generally starch, glue, wax, casein, clayetc are used. It is not a permanent finish. 9.5 Bleaching Bleaches areusedto rendercolouredordiscolouredfabricswhite. Bleaches are used inlaundering to remove stainsthat do not respondto normalwashing. Bleaches should not be used as cleansers. It is not possible to bleach dirty laundry. Bleaching agents can be dividedinto two classes 1. Oxidizing bleach
  • 106. Commercial GarmentTechnology182 2. Reducing bleach. Oxidizingbleachsupplyoxygenthat combineswithstainsto formacolorless compound. Normal as well as stained fabrics can be oxidized so the bleach must be incontact with the fabric onlytillthe stain is removed. Longer contact willweakenthe fibric. Reducing bleachesworkbyremoving oxygenfromthecolouring matter of the stain. Conclusion Finishing alters the surface ofa fabric and therefore its look and feel. The finishing processes are required to make the materials attractive. They also improvetheirserviceability.Finishingstraightensthefabricandbringsitto required dimensions. I. Test your understandings State whether the statement is true or false 1. Calendaring is an ironing process. (T/F) 2. Singeingremoves the short fibers fromcloth. (T/F) 3. Tentering is not a finishingprocess. (T/F) 4. Caustic soda is used in mercerizingto give silkyluster to fabrics. (T/F) 5. 5-10% ofcaustic soda is used inmercerizing process. (T/F) 6. Bleaches are used in laundryto remove stains. (T/F) 7. Bleaching agents can be divided into 3 classes. (T/F) 8. Oxidizing bleachsupplies nitrogenthat combines’withstains to produce colorless compound. (T/F) Short Answer Type Questions 1. What is calendaring? 2. What are finishes? 3. What is singeing? 4. What is tentering? 5. What is mercerizing? 7. What are finishes?Write about calendaring and singeing?
  • 107. Paper - II Textile Science 183 Long Answer Type Questions 1. What are the different typesofcalendaring finishes givento different types oftextiles? 2. What finishappealto touch? Explain. 2. Differentiate betweennapping and parchmentization? 4. Howis burnt out finishdifferent fromparchmentisation? Answers for Test yourunderstanding 1. True 2. True 3. False 4. True 5. False-18-20% is used 6. True 7. False- 2 classes 8. False - Oxygen 9. True
  • 108. Commercial GarmentTechnology184 References 1. Textile fiber and their use - Hess 2. Fundamentals oftextiles and their care - Susheela Dautyagi 3. Household textiles and haundrywork - Deerga Deulkar 4. Modern textiles - DorothyLyle 5. The standard hand book ofTextiles -AJ Hall 6. Introduction toTextiles . E.E. Stout 7. Textile Fabrics and their selection 8. Clothing for moderns - Erwinand Kichener