Tannery

Tanning is the process of making leather, which does not easily decompose, from the skins of animals. Often this uses tannin, an acidic chemical compound. Coloring may occur during tanning. Tanning leather involves a process which permanently alters the protein structure of skin so that it cannot ever return to rawhide.

In ancient history, tanning was considered a noxious or "odiferous trade" and relegated to the outskirts of town, amongst the poor. Indeed, tanning by ancient methods is so foul smelling that tanneries are still isolated from those towns today where the old methods are used. Ancient civilizations used leather for waterskins, bags, harnesses, boats, armour, quivers, scabbards, boots and sandals.

Tanning was being carried out by the South Asian inhabitants of Mehrgarh between 7000–3300 BC. Skins typically arrived at the tannery dried stiff and dirty with soil and gore. First, the ancient tanners would soak the skins in water to clean and soften them. Then they would pound and scour the skin to remove any remaining flesh and fat.

Next, the tanner needed to remove the hair fibers from the skin. This was done by either soaking the skin in urine, painting it with an alkaline lime mixture, or simply letting the skin putrefy for several months then dipping it in a salt solution. After the hair fibers were loosened, the tanners scraped them off with a knife.

Once the hair was removed, the tanners would bate the material by pounding dung into the skin or soaking the skin in a solution of animal brains. Among the kinds of dung commonly used were that of dogs or pigeons. Sometimes the dung was mixed with water in a large vat, and the prepared skins were kneaded in the dung water until they became supple, but not too soft. The ancient tanner might use his bare feet to knead the skins in the dung water, and the kneading could last two or three hours.

MODERN METHOD The first stage is the preparation for tanning. The second stage is the actual tanning and other chemical treatment. The third stage, known as retanning, applies retanning agents and dyes to the material to provide the physical strength and properties desired depending on the end product.

The fourth and final stage, known as finishing, is used to apply finishing material to the surface or finish the surface without the application of any chemicals if so desired. Preparing hides begins by curing them with salt. Curing is employed to prevent putrefaction of the protein substance (collagen) from bacterial growth during the time lag that might occur from procuring the hide to when it is processed.

Curing removes excess water from the hides and skins using a difference in osmotic pressure. The moisture content of hides and skins gets greatly reduced. In wet-salting, the hides are heavily salted, then pressed into packs for about 30 days. In brine-curing the hides are agitated in a salt water bath for about 16 hours.

Generally speaking, curing substantially reduces the chance of spoilage by bacteria. Curing can also be done by preserving the hides and skins at a very low temperature. In a process known as soaking, the hides are then soaked in clean water to remove the salt and increase the moisture so that the hide or skin can be further treated.

Liming process of hides and skins After soaking, the hides and skins are taken for liming: treatment with milk of lime (a basic agent) that may involve the addition of "sharpening agents" (disulfide reducing agents) like sodium sulfide, cyanides, amines etc.

The objectives of this operation are mainly to: Remove the hairs, nails and other keratinous matter Remove some of the interfibrillary soluble proteins like mucins Swell up and split up the fibres to the desired extent Remove the natural grease and fats to some extent Bring the collagen in the hide to a proper condition for satisfactory tannage

Chelsi Leather and Services Inc. produces leather from different hides that are specialized for footwear, bags, belts, accesories, upholstery, and automative purposes. These hides include cow, carabao (buffalo), goat, fish, snake, ostrich, and crocodile. However, it does not limit itself to these hides as it can service to any kind of skin. Chelsi offers genuine top-class leather of all kinds. It aims not only to scrutinize leather quality, but also to ensure affordability.

Chelsi products Adelinda (salmon) Ladies’ rectangle handbag with division. Zippered pocket at the back. Made from fishskin leather Dimensions: 11 x 8 x 4.5 in. Colors: brown, tan, salmon PHP 2,500.00Price: Vince Messenger bag made from cow hair-on leather PHP 1,800.00Price:

Bianca Gray crocodile embossed cow leather. Hermes inspired. PHP 2,000.00Price: Aderyn (red) Multi-colored cow leather wallet clutch with snakeskin design in front. Removable straps. Many pockets. PHP 1,800.00Price:

Robalyn (tan) Card holder made from cow leather. Has 2 single card slots on each side and 1 wide card slot. Dimensions: 10 x 16 cm Colors: black, brown, tan, croco PHP 350.00Price: Robalyn (croco) Card holder made from cow leather. Has 2 single card slots on each side and 1 wide card slot. Dimensions: 10 x 16 cm Colors: black, brown, tan, croco PHP 350.00Price:

Romilda (white) Men’s wallet made of water snake skin PHP 500.00Price: Romana (red) Ladies’ wallet made of water snake skin PHP 800.00Price:

Gray Jar (small) PHP 1,200.00 Price: Chest PHP 8,500.00 Price:

Lailie (brown) Cuffed gladiator sandals made from nubuck leather and snake skin Size: PHP 800.00Price: Laila (royal blue) Made from cow nubuck leather PHP 800.00Price:

Tannery

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Tannery