The chrome tanning process is the most recent leather tanning treatment. Historically the first chrome-tanning processes date back to the late nineteenth century, to be patented in 1910. In leather industry a significant development of chrome-tanning process occurred in the post-war period, when this process were introduced for the industrial production of large amount of leathers.
How does the chrome tanning process work?
This type of tanning is based on the Trivalent Chromium, which is able to create very stable bonds with the collagen of the leather, blocking the natural processes of decomposition. Prior to the introduction of the trivalent chromium into the leather, several steps are required to produce a tannable hide. Leather is treated with a solution of common salt and acid, this will prepare the material to be penetrated by Trivalent Chromium. After the leather has been prepared, it is immersed in a solution containing chromium salts. Once the desired level of penetration of chrome into the substance is achieved, the pH of the material is raised again to complete the process.
The chrome tanning process is much faster than vegetable tanning, in fact the duration can vary from a minimum of 3-6 hours to a maximum of 20-24 hours.
At the end of the tanning process the leather takes on a Green-Blue color and for this reason it is also called "Wet Blue", as it is still wet and blue.
The "Wet Blue" is then subjected to subsequent finishing operations, to obtain colored or crust leathers, ready to be used in manufacturing industry.
Why chrome tanning process is so popular?
It is estimated that 80-90% of the leathers used in manufacturing industry are chrome-tanned. This is due to the fact that the chrome tanning process is much faster and more industrialized than traditional vegetable tanning, it allows to get more stable, uniform and resistant leathers that can then be processed or finished obtaining different types of products for manufacturing industries as fashion, automotive, furniture, etc.
Furthermore, the production costs of chrome-tanned leather are much more competitive than those required to produce vegetable-tanned leather. This allows to have products that are cheaper and more suitable for use on items of wide productions.
Is possible to dye a chrome tanned leather?
Absolutely yes, just choose the right leather dye for leather crafters. Chromium-tanned leathers generally have much more uniform characteristics than vegetable-tanned leathers, and ease of penetration during the leather dyeing process. If you want to use a chrome leather to customize, it is always recommended to start with a crust leather, which has not undergone finishing processes. This choice can be recommended when you need to produce standard items or large-scale items.
But if you want to create a traditional leather crafting items, you should always use a natural veg-tanned leather.