Tanning
Tanning treats animal hides with chemical or plant-derived agents to stabilize their collagen, producing leather resistant to decay and heat.
Collagen: A structural protein whose triple-helical molecules form the main framework of animal skin. Tanning agents bind to or alter this protein to resist decay and shrinkage.
Animal hide: The skin removed from an animal, consisting chiefly of collagen-rich dermal tissue. It is the raw material that tanning converts into leather.
Glove leather: Soft, pliable leather made for gloves and other close-fitting goods. Tanning and finishing choices are selected to preserve flexibility and softness.
Tannery: A workshop or industrial facility where animal hides are processed into leather. Tanneries concentrate the water, labor, and chemical operations involved in tanning.
Tannins: Plant polyphenols that bind proteins and occur in many leaves, bark, and fruits. These compounds cross-link hide proteins in traditional vegetable tanning.
Liming (leather processing): A hide-treatment step using alkaline lime, often with sulfide, to loosen hair and swell the skin. Liming opens the hide structure before tanning agents need to penetrate it.
Sole leather: Dense, firm leather traditionally used for shoe soles. Vegetable tanning can create the stiffness and wear resistance required for soles.
Tanning industry: The network of businesses that converts animal hides into leather and related products. Industrial tanning scaled a craft into a global supply chain.
Chrome tanning: A tanning method that uses chromium(III) salts to stabilize animal hides. Chromium complexes bind collagen rapidly, producing leather with high heat resistance.
Fleshing: The removal of flesh and fat from the underside of a hide or skin. It clears tissue that would obstruct uniform chemical treatment.