CLANAE 15.1—Tanning and finishing of leather; manufacture of leather goods and saddlery

Where 15.1 sits

1. C Manufacturing industry
2. 15 Tanning and finishing of leather; manufacture of leather goods, saddlery and footwear and of its parts
3. 15.1 Tanning and finishing of leather; manufacture of leather goods and saddlery

Contains 2 narrower codes

• 15.11 Tanning and finishing of leather
• 15.12 Manufacture of suitcases, handbags, saddlery and leather goods n.e.c.

What 15.1 includes

• The tanning process gives hides new characteristics and transforms them into leather. It comprises the following stages: hide preservation, hide preparation, liming, and the actual tanning process.
• Hide preservation is an operation in which the animal's hide is treated with chemicals, such as zinc chloride or formaldehyde, to remove traces of blood and sterilize it.
• Preparing the hides for tanning involves soaking them in water, which restores their flexibility and removes dirt and impurities. Next comes fleshing, which is done by hand or machine to remove any remaining flesh from the hide. Finally, greening is carried out using caustic soda, sodium sulfide, or sodium bisulfite, which restores the leather's flexibility for the subsequent stages.
• Liming removes hair and any other epidermal secretions. This process involves immersing the hides in quicklime, followed by hair removal, and finally, deliming. If chrome tanning is used, a bath of calcium chloride, hydrochloric acid, and water is used instead of lime.
• Tanning in general involves immersing the hides resulting from the previous processes in substances such as: tannin or quebracho extract with sodium chloride (vegetable tanning), chromium salts (chrome tanning), cod liver oil, linseed oil, or soybean oil (oil tanning).
• Leather finishing operations include: greasing or oiling, which is done using oils and fats, melted tallow, wax, resins, and hydrocarbons; and skiving, which is carried out by passing the leather through a scraping machine that uses helical blades to cut the surface, giving it a uniform thickness. The bleaching process uses baths containing sodium carbonate, sulfuric acid, and sodium bisulfite. The leather's surface luster is achieved by smoothing and rubbing it with a glass cylinder.

15.1 in other systems