Leather and Tanning

All our leather products are produced in Italy in the local tanneries of Santa Croce. We use a mixed tanned leather, a combination between vegetable and chemical tanning, just to achieve the best performance for our products, in terms of durability and best quality results.

Before tanning, the skins are dehaired, degreased, desalted and soaked in water over a period of six hours to two days.
Historically this process was considered a noxious or "odoriferous trade" and relegated to the outskirts of town.
In the past, tanning used tannin, an acidic chemical compound from which the tanning process draws its name, derived from the bark of certain trees.
An alternative method, developed in the 1800s, is chrome tanning, where chromium salts are used instead of natural tannins.


Preparation
The steps in the production of leather before tanning are collectively referred to as beamhouse operations. They include, in order, soaking, liming, removal of extraneous tissues (unhairing, scudding and fleshing), deliming, bating or puering, drenching, and pickling.

Vegetable tanning
Vegetable tanning uses tannins (a class of polyphenol astringent chemicals), which occur naturally in the bark and leaves of many plants. Tannins bind to the collagen proteins in the hide and coat them, causing them to become less water-soluble and more resistant to bacterial attack. The process also causes the hide to become more flexible. The primary barks processed in bark mills and used in modern times are chestnut, oak, redoul, tanoak, hemlock, quebracho, mangrove, wattle (acacia; see catechol), and myrobalans from Terminalia.
Hides that have been stretched on frames are immersed for several weeks in vats of increasing concentrations of tannin. Vegetable-tanned hide is not very flexible. It is used for luggage, furniture, footwear, belts, and other clothing accessories.

Chrome tanning 
Chromium(III) sulfate has long been regarded as the most efficient and effective tanning agent. Chromium compounds of the sort used in tanning are less toxic than hexavalent chromium, although the latter arises in inadequate waste treatment. Before the introduction of the basic chromium species in tanning, several steps are required to produce a tannable hide. The pH must be very acidic when the chromium is introduced to ensure that the chromium complexes are small enough to fit between the fibers and residues of the collagen. Once the desired level of penetration of chrome into the substance is achieved, the pH of the material is raised again to facilitate the process. This step is known as basification. Chrome tanning is faster than vegetable tanning (taking less than a day for this part of the process) and produces a stretchable leather which is excellent for use in handbags and garments.


Alternative tanning
Wet white is a term used for leathers produced using alternative tanning methods that produce an off-white colored leather. Like wet blue, wet white is also a semifinished stage. Wet white can be produced using aldehydes, aluminum, zirconium, titanium, or iron salts, or a combination thereof.

Post-tanning finishing
Depending on the finish desired, the leather may be waxed, rolled, lubricated, injected with oil, split, shaved, or dyed.
Our leather is covered with a special resin that makes the back of the skins smoother and well refined, avoiding chemical product so you can wear safely our accessory on your skin.