Copyright 2009 © Chemical Industry Zupa ad Krusevac
LEATHER PROCESSING AGENTS
Production program Leather processing agents of Chemical Industry "Župa" ad Kruševac includes:
HROMIBAS - 33
CHEMICAL DATA Hromibas 33 Cr2O3 25±1% (powder) 17±1% (liquor); Basicity 33±1% ; Na-sulphate 23-24% (powder); 15-17% (liquor)
APPEARANCE Green powder - green liquid.
PROPERTY AND APPLICATION When in the form of green powder, Hromibas 33 is well souble in cold and warm water.
The product is added to the float for picking undissolved or in the form of a solution.
It is added at 6-8% calculated to the weight of pelt. In order to profit the stability of freshly dissolved basic chrome sulphate, it is recommended to start with basifying already 30 minutes after adding tanning material. Basifying agents: soda, sodium carbonate or sodium sulphate are usually dissolved in water and added in more portions with 60 to 120 minutes. If basifyed with magnesium oxide, it is added in powder in one or more portions.
PACKING Hromibas 33 powder is packed in double bags, inside PE, outside PP, or in natron bags. Hromibas 33 liquor is transported in adequate tank cars.
ŽUPACHROME CM
CHEMICAL DATA Cr2O3 7-8%
APPEARANCE A green - grey powder.
PROPERTY AND APPLICATION Župachrom - CM is reactive chrome tanning agent, an integral part of chrome tanning process with high float exhaustion. It acts as a fixing and self-basifying agent, so that no basifying is necessary and the end pH 3.9-4.1 is obtained.
This material is adapted for the production of all types of chrome leathers. No special preliminary steps is necessary for its application. The tanning has been done in combination with basic chrome sulphate of basicity 33% Sch.
While preparing chrome tanning agent with ŽUPACHROM CM, the product tending ro better level of use, the most important is to determine:
- float quantity
- temperature
- pH value
- chrome oxide quantity
Next condition of work are recommended:
- absolutely delimed andbated leather, pH of leather 7.8 - 8.0
- PHPH - colourless, throught
- 40% water T=26°C-27°C
- 5% NaCl 10'(5-7Bë)
- 0,7% HCOOH (1:5) 15'
- 0,8% H2SO4 (1:10) 120'
- pH=2,9-3,1 throught BC=yellow
Tanning:
- 4% BCS 33% Sch 60'
- 2.2% Zupachrom CM 540'
- T=43°C boiling test 98-100°C pH=3.8-4.1
PACKING In double bags, inside PE, outside PP, or in natron bags.
