The pre-tanned calf hide, also known as wet-blue, must undergo a number of chemical processes – each with a thorough quality assessment. The steps are carried out in a revolving drum, as is true for the entire tanning procedure.
All of this involves a number of very different and complex treatments, which are linked together but also parallel to each other. For example, neutralization, re-tanning, dyeing and fat liquoring. Between these procedures, washing and rinsing operations take place.
All of these activities can be summarized under the segment “Dyeing“, though the actual coloring represents only a very small part of the entire process. Actually, “Dyeing“ which represents the sum of all wet operations, gives the leather the specific properties, such as softness, stretch, durability or water resistance and allows, through diversified process monitoring, a different end product with the same procedure. It is possible therefore to produce firm shoe leather as well as soft upper leather through the same tanning process.