Dyeing Faults & Remedies
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This document discusses common dyeing faults in textiles, their causes, and remedies. It describes several types of dyeing faults such as uneven dyeing, crease marks, batch-to-batch shade variation, and roll-to-roll variation. For each fault, it outlines potential causes such as uneven pretreatment, improper dosing of dyes and chemicals, fluctuations in temperature, and issues with dyeing machinery. The document then provides recommendations for remedies, including ensuring even pretreatment, maintaining standard dyeing procedures, controlling dyeing machinery properly, and using consistent dyes and chemicals. It aims to help overcome dyeing faults and improve the quality of dyed fabrics.
Dyeing Faults & Remedies
- 1. Textile Engineering ( B.Sc. in Textile Engineering ) Topic: Dyeing faults & Remedies
- 2. Presented by: Mazharul Islam. B.Sc. in Textile Engineering. Dept. of Wet Process Engineering (WPE). PTEC _ Session 2015-16 (10th Batch). Email: tex.mazharul@gmail.com 22% 21% 23% 11% 23% DYEING FAULTS (%) Diverse Faults Pretreatment fault Bio & m/c faults finishing fault dyeing and printing fault
- 3. Dyeing Faults • Uneven dyeing • Crease/wrinkle mark • Batch to Batch Shade variation: • Patchy dyeing effect: • Roll to roll variation or Meter to Meter variation The faults which are visible after dyeing are called dyeing faults. This faults describes the quality of fabric. So the over come from this fault we have to know the causes and their remedies of these dyeing faults. Example of dyeing faults:
- 4. • Dye spot • Softener Mark • Running Shade • Fabric Hole Some other dyeing faults: • Yellow spot. • Long mark • Loop mark • Dhappa spot. • Iron spot • Out color • Enzyme dust • Fly we • Brush problem • Water spot • Soda spot. • Lycra out. • Out color. • Patta fault.
- 5. 1. Uneven dyeing: Causes: Uneven pretreatment (uneven scouring &bleaching). Improper color dosing. Correct pH value not maintained. Water hardness Using dyes of high fixation property. Uneven heat-setting incase of synthetic fibers. Lack of control on dyeing m/c (like - m/c speed, Temperature of the process, Dossing time, M:L ratio, improper washing after dyeing)
- 6. Remedies: By ensuring even pretreatment. By ensuring even heat-setting in case of synthetic fibers. Proper dosing of dyes and chemicals. Proper controlling of dyeing m/c 2. Crease mark: Causes: Poor opening of the fabric rope Shock cooling of synthetic material
- 7. If pump pressure & reel speed is not equal Due to high speed m/c running. Lower rate rinsing and cooling the temperature. Reducing the machine load Remedies: Maintaining proper reel speed & pump speed. Low rate rising and cooling the temperature Reducing the m/c load Higher liquor ratio
- 8. 3. Batch to Batch Shade variation: Causes: Use of different brands dyes and chemicals Fluctuation of Temperature. Improper dosing time of dyes & chemicals. Batch to batch weight variation of dyes and chemicals. Dyes lot variation. Improper reel speed, pump speed, liquor ratio. Improper (poor) pretreatment.
- 9. Remedies: Use standard dyes and chemicals. Maintain the same liquor ratio. Follow the standard pretreatment procedure. Maintain the same dyeing cycle. Identical dyeing procedure should be followed for the same depth of the Shade. Makesurethattheoperatorsaddtherightbulkchemicalsatthesameti meandtemperaturen the process. The pH, hardness and sodium carbonate content of supply water should check daily.
- 10. 4. Patchy dyeing effect: Causes: Entanglement of fabric. Faulty injection of alkali. Improper addition of color. Due to hardness of water. Due to improper salt addition. Dye migration during intermediate dyeing. Uneven heat in the machine, etc
- 11. Remedies: By ensuring proper pretreatment. Proper dosing of dyes and chemicals. Heat should be same throughout the dye liquor. Proper salt addition.
- 12. 5. Roll to roll variation or Meter to Meter variation: Causes: Poor migration property of dyes. Improper dyes solubility. Hardness of water. Faulty m/c speed, etc Remedies: Use standard dyes and chemicals. Proper m/c speed. Use of soft water
- 13. 6. Dye spot: Causes: Improper Dissolving of dye particle in bath. Improper Dissolving of caustic soda particle in bath. Remedies: Need to clean the m/c properly. By proper dissolving of dyes & chemicals By passing the dissolved dye stuff through a fine stainless steel mesh strainer, so that the large un-dissolved particles are removed
- 14. 7. Softener Mark: Causes: Improper mixing of the Softener. Improper running time of the fabric during application of softener. Entanglement of the fabric during application of softener Remedies: Maintaining proper reel speed & pump speed. Proper Mixing of the softener before addition. Prevent the entanglement of the fabric during application of softener
- 15. 8. Fabric Hole: Causes: More acid in dyeing section. High temperature. Remedies: Use standard acid. Proper dossing of Acid.
- 16. 9. Chemical spot: Causes: Use low quality de-formation agent. Improper dossig. Access chemical use in softening machine Remedies: Use good quality de-formation agent. Proper dossing Appropriate chemical use in softening machine
- 17. 10. Soda spot: Causes: Not carefully use of NaOH. Alkalinity. Remedies: Carefully use of NaOH. Proper neutralization.
- 18. <Md Mazharul Islam> WPE dept. 10th Batch, PTEC. 1 8 YouTube References: • A.D Broadbent, Basic Principle of Textile Coloration, 2001, England • M.F Hossain, Practice of textile coloration, Vol 01.2007, Dhaka. • Web: DocPlayer.net , Study of different types of dyeing faults, Causes and remedies. • Web: textilelearner.blogspot.com
- 19. Thank You ! 19