Leather is the main raw material for our company’s work. Through it, we have built a legacy of more than 25 years in the market, delivering differentiated articles, thanks to the various production techniques achieved, allied to a modern technological structure. Along this trajectory, we learned a lot about this material so noble and unique. It is a rich universe and there’s always something new to learn.
By definition of the The Brazilian Technical Standards Association (ABNT), leather is a material that comes exclusively from animal skin, when considered legitimate. It is composed of an extremely rich texture of collagen fibers, which will go through a series of processes to become flexible and soft, thus being suitable for industrial handling. After this series of procedures, the leather is free from decomposing microorganisms.
As we have already highlighted in other materials, as it is a natural product, the word “leather” is protected by law, therefore, its use to describe industrialized products that are not of animal origin is prohibited.
The type of leather that we work with in our processes is Vacum, that is, of bovine origin. Out of curiosity, the required nubuck and suede are also from bovine hides, which in turn is divided into two parts: grain and scrape. It serves as a basis for finishing aimed at the manufacture of clothing items and accessories, such as bags, shoes, wallets, belts, among others.
Types of tanning
The best known process aimed at transforming animal skin into a stable, durable and resistant material is tanning. It is responsible for eliminating decomposing microorganisms and increases the hydrothermal stability of the skins. Only after this procedure can the material actually be called leather.
There are several known tanning modalities and each one has its purpose. The best known and most common is the mineral, which is the tanning made using trivalent chromium salts. When tanned only through this process, the leather is called wet-blue. In this process in particular, the raw material gains elasticity, softness, low specific weight and are the most used for clothing.
Another method recurrent in tanneries is the vegetable (or organic) process, which consists of using vegetable tannins, combined or not with synthetic tannins, for processing. After being treated, these pieces tend to have greater specific weight, less stability to washing, and are more aimed at furniture and accessories that do not require a more malleable leather.
Mixed tanning is carried out using synthetic-based products, such as glutaraldehyde and phenols, which provide greater resistance to leather and washing. And, finally, the preservation tanning is carried out through superficial greases. In addition to the tanning processes, leather can also undergo retanning, where characteristics such as filling, elasticity and strength are defined.
It’s a fascinating subject, right? We love talking about leather, its properties, treatments and applications! We always seek to bring the most refined finishes, where quality stands out to the first look. Keep following Courovale for these and other tips!