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The earliest crude leathers were made by first immersing the raw hides and skins in a fermenting solution of organic matter in which bacteria grew and attacked the hides or skins, resulting in a loosening of the hair or wool and some dissolving out of skin protein. The hair or wool was then scraped off with primitive blunt stone or wooden scrapers and fat or meat still adhering to the flesh side was removed in a similar manner.
Tanning, the conversion of pelt into leather, was done by dusting the raw stock with ground up bark other organic matter and placing them in shallow pits or vats of tannin solution.Further additions of ground bark, were made from time to time until the tannin solution had penetrated right through the skin structure, taking up to two years for very thick hides. The leather was then hung up for several days in open sheds. The dressing of the leather involved paring or shaving it to a level thickness, coloring, treatment with oils and greases, drying and final treatment of the grain surface with waxes, proteins such as blood and egg albumins, and shellac to produce attractive surface finishes.
During the Middle Ages leather was used for all kinds of purposes such as: footwear, clothes, leather bags, cases and trunks, leather bottles, saddlery and harness, for the upholstery of chairs, and couches, book binding and military uses. It was also used to decorate coaches, sedan chairs and walls.The majority of the leather was tanned with oak bark but soft clothing, gloving and footwear leathers were tanned with alum, oil, and combinations of these two materials.With the discovery and introduction of basic chemicals like lime and sulphuric acid, tanners gradually abandoned their traditional methods and leather production slowly became a chemically based series of processes.
The growth of industrialization in the 18th and 19th centuries created a demand for many new kinds of leathers, e.g., belting leathers to drive the machines being introduced into industry, special leathers for use in looms in the textile industry, leathers for use as diaphragms and washers, leathers for use in transport and for furniture upholstery.
At the end of the nineteenth century, the invention of the motor car, modern roads, new ranges of coal tar dyestuffs, the demand for softer, lightweight footwear with a fashionable appearance, and a general rise in the standard of living created a demand for soft, supple, colorful leather. The traditional vegetable tanned leather was too hard and thick for these requirements and thus, the use of the salts of the metal chromium was adopted and chrome tanning became the tannage for modern footwear and fashion leathers. It produces soft, supple, beautiful and fine leathers, reflecting the way we live.
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