Tanning is the important process in working procedure. It is a physical and chemical process to make rawhide to leather through tanning agent. So how is the leather tanned?
There are two ways for tanning: vegetable tanning and chrome tanning.
The oldest tanning method is that using natural material such as plants, fruits and vegetables tanning agent. The animal skin should be soaked in vegetable tanning agent repeatedly for about one or two months, even more than ten months. Vegetable tanned leather does not contain harmful substances and can be contact with the skin directly. The Italian leather’s techniques and quality are the best. So it has the great reputation in the leather market.
Feature: The surface of vegetable tanned leather is shallow brown. It has a hard texture and muscle. It has a small range flexibility, good smell, air permeability and water water-absorbing quality. It will be soft when absorb water. It has high plasticity for easy processing and suitable for leather carving. But the oil in leather will run off with the evaporation of water. So the leather will become hard and lose luster, with the time grew, it will become fragile and appear even crack fracture.
Chrome tanning is the most common tanning method now. It finished by soaking in the chemical raw materials tanning agents for about a day. The production is very quick and simple. It is the foundation of industrialization for leather industry. Now about eight to ninety percent leather of the market is chrome tanned leather. The price is cheap, but long-term exposure to chrome tanned leather will have a bad effect to the skin.
Feature: Combination dyeing processing, high soft, waterproof, color lasting, high heat resistance, but not durable and not natural smell and taste with chemicals.
There are other methods for tanning leather: wet white tanning, latigo tanning, brain tanning, aldehyde tanning, chamois tanning, chamois tanning, combination tanning, aldehyde tanning.
Tanning process is mainly divided into the following process:
- Preparatory process: soaking, degreasing and washing, cutting.
- Tanning process: the raw hides and clean tanning agents.
- Finishing process: fat liquoring, moisture regain, staking, reshaping the whole hair.