1. COMPOSITION

SYNTEX CRA is a complex based on Aluminium and Chromium sulphates of high basicity.

2. PHYSICAL and CHEMICAL PROPERTIES

Aspect : spraydried powder

Colour : green

pH (10 % solution) : 3.1 +- 1.0

Total solids : 94 %

Aluminium Oxide : around 10 %

Chromium Oxide : around 15 %

3. CHARACTERISTICS

SYNTEX CRA is used in chrome retannage to improve the leather in confering a denser and stickier consistency which renders the buffing operation and makes the dyeing one easier. SYNTEX CRA is also recommended for the retannage of white leathers.

In retannage, it is possible to obtain a retraction temperature of 100°C in increasing the basification pH up to 4.2 - 4.5 without risk of precipitation. Good exhaustion of tanning agents is obtained and Aluminium salts hydrolysis is stopped. The quality of effluents is improved due to the low residual Chromium content.

Due to its fixing powder on cationic substances, SYNTEX CRA is suitable for the retannage of vegetable tanned leathers. However, being a cationic complex, it has to be used in sandwich for through-dyeing, i.e. :

- through-dyeing

- use of SYNTEX CRA in a new bath

- second dyeing in order to strengthen the shades

For sueded woolled skins, SYNTEX CRA can be used in mixture with SYNTEX CFCR for the obtention of light skins of pale colour with very good improvement of wool which is no more dyed nor altered.

On the flesh side, the characteristics brought out by the Chromium/Aluminium complex allows to obtain very fine shearing and bright shades.

4. APPLICATIONS

- Garment leather : 3 % SYNTEX CRA on pickled skins ;

- Retannage of chrome leather for suede : 4 to 5 % SYNTEX CRA (% on shaved skins) ;

- Retannage of leathers pre-processed with vegetable and synthetic tannins :

4 to 6 % Chromium Sulphate 33 % Sch.

4 to 6 % SYNTEX CRA

Technical Data Sheet

Edition : 19.03.01

Code : IRICRA

Index : 0

Document PC.073/A

This information does not constitute a specification. It is given in good faith
Without guarantee or liability. We are at your disposal for any further technical details.