one of the most expensive process in leather industry
Crusting is when the hide/skin is thinned, re-tanned and lubricated. Often a coloring operation is included in the crusting sub-process. The chemicals added during crusting have to be fixed in place. The culmination of the crusting sub-process is the drying and softening operations. Crusting may include the following operations:
· Wetting back - semi-processed leather is re hydrated.
· Sammying - 45-55%(m/m) water is squeezed out the leather.
· shaving - the leather is thinned using a machine which cuts leather fibers off.
· Neutralization - the pH of the leather is adjusted to a value between 4.5 and 6.5.
· Re-tanning - additional tanning agents are added to impart properties.
· dyeing - the leather is colored.
· fat liquoring - fats/oils and waxes are fixed to the leather fibers.
· filling - heavy/dense chemicals that make the leather harder and heavier are added.
· stuffing - fats/oils and waxes are added between the fibers.
· stripping - superficially fixed tannin's are removed.
· whitening - the color of the leather is lightened.
· fixation - all unbound chemicals are chemically bonded/trapped or removed from the leather
· setting - area, grain flatness are imparted and excess water removed.
· drying - the leather is dried to various moisture levels (commonly 14-25%).
· conditioning - water is added to the leather to a level of -28%.
· softening - physical softening of the leather by separating the leather fibers.
buffing - abrasion of the surfaces of the leather to
Why Ostrich Leather is popular for its DURABILITY?
Ostrich leather is popular and well known for its Durability; it consists of three layers of interwoven fibers, which make it resistant to stretching, another fact to make it one of the most durable leather is the oils that keep it from drying out and that makes it even softer.
Ready Crust waiting for dye process ;
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