LEATHER SCIENCE: Post Tanning Operations
Crust leather obtained after post tanning operations is a higher added value skin and hides already tanned ready for the finishing stage. The semi-tanned wet-blue leather undergo final tanning to produce crust leather. The distinct feature of this product from the wet-blue leather is that it has visible physical properties such as size, thickness, fullness, looseness of grain and grain damages. It is rather a product of better tensile and tearing strength, chrome and fat content etc. than wet-blue leather. “Crust is also known as unfinished leather ” and It is used by the leather finishing industries. The different methods of making Crust are given below: A. Chrome-Retan Process B. Semi Chrome Process Post tanning Oprations for Chrome-Retan Crust Leather PREPARATION FOR POST TANNING After the completion of Chrome tanning, the leathers have to pass through few operations to prepare them for Post tanning operations further. Following are the preparatory stages: 1...