The leathers and cowhides we use are processed in a labor and time intensive process. All hides go from soaking to finishing through a certified, environmentally friendly vegetable tanning process.
Tanning is one of the oldest culture techniques of mankind; the durability of hides was already optimized in prehistory using selected substances. Read below to learn about the animal skin as one of the first recycling products, and send us a message if you have further questions or suggestions. The first stage is the preparation for tanning, followed by the so-called soaking. The actual tanning takes place at the third stage, the fourth stage is used to apply finishing material to the surface or finish the surface without the application of any chemicals if so desired.
Step 1 “Preparation”: Preparing hides begins by curing them with salt. Curing is employed to check putrefaction of the protein substance (collagen) because of the chance of bacterial infection due to the time lag that might occur from procuring to processing. It removes the excess water from the hides and skins where water flows from inside because of difference in osmotic pressure. Thus the moisture content of hides and skins get greatly reduced. In wet-salting, the hides are first treated with carbonate and 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, methods employed for curing greatly make the chance of bacterial growth unfavorable; they also help preserving the hides and skins at a very low temperature.
Step 2 “Soaking”: The hides are then soaked in clean water to remove the salt and mainly to bring back the moisture content to a desirable level so that the hide or skin can be treated in an aqueous medium. This process sometimes involves the employment of a hydrating agent along with water in a very low percentage for hides and skins which have become very dry. Following that, the soaked hides and skins are taken for the next operation where these are treated with milk of lime. Here, the objective is mainly to remove hairs, nails and the natural grease as well as to bring the collagen to a proper condition for satisfactory tannage.
Step 3 “Tanning”: Tanning can be performed with either vegetable or mineral methods; our partners exclusively employ vegetable procedures based on tannin (this is where the name tanning comes from). Tannin occurs naturally in bark; the primary barks used in modern times are chestnut, oak, tanoak, hemlock and mangrove. Hides are stretched on frames and immersed for several weeks in vats of increasing concentrations of tannin. Vegetable tanned hides are flexible and can be used for luggage and furniture, among others for our seat covers and exclusive home accessories.
Step 4 “Finishing”: Depending on the finish desired, the hide may be waxed, rolled, lubricated, oiled, split, shaved and, of course, dyed. Suedes, nubucks, etc. are finished by raising the nap of the leather by rolling with a rough surface.
(C) WEINBAUMS, leathernet.com and wikipedia.com