Synthetic tanning agents or Syntans are one of the most important and versatile leather auxiliaries that are needed for the manufacture of good quality and special types of leathers. These synthetic tanning agents bring about a considerable improvement of the handle, fullness, tightness of grain and buffing properties, besides preserving the chrome character of the leather. Some syntans like INDOTAN MB, INDOTAN 536, INDOTAN 540, INDOTAN RE 98 and INDOTAN RE 100 produce white leathers with good light fastness.
Synthetic tanning agents are classified under these broad categories:
a) Auxiliary Syntans
b) Intermediate Syntans
c) Replacement Syntans
a) Auxiliary Syntans
These are further subdivided into two types – neutral and acidic. Neutral Syntans are mainly used as tan assists. If used in the neutralisation of chrome leather, as described above, they assist in achieving controlled penetration of vegetable extract giving a smooth grain and a light colour. They also act as dispersing agents for vegetable extracts and mordents and dispersing agents for dyestuffs.
Acidic Syntans are used as bleaching agents for chrome leather and for leveling dyestuffs.
Axuiliary syntans have a limited tanning power and therefore can be used on unneutralised chrome leather without any danger of drawing grain. This class of syntans is never used on retanning; they are either used with vegetable extracts or with resin Syntans like INDOTAN-540 or INDOTAN MB.
ALUMINIUM SYNTANS-INDOTAN A-31:
Specially Masked Aluminium syntan being chrome shaver. It can cut down effluent due to chrome by exhibiting the property of exhausting chrome in bath. When used with chrome, the Cr+++ in the exhaust liquor is found only 92ppm which is extremely low, The uniform penetration of chrome and uniform colour of wet blue can be achieved. No Extra cost imput since this is a low valued product.
