Description

KEMCOT-LG is a special liquid product for providing aluminum with a green chemical film or coating of the surface conversion type, for protection against corrosion and improvement of paint adhesion.

Pre-Cleaning:

Before using KEMCOT-LG surfaces must be free from grease, soils and oxides. RADOL 22-22F (5% in the water at room temperature) is recommended for cleaning and deoxidizing. Parts must thoroughly be rinsed with clean water after cleaning. Rinse tanks should be kept pure and refilled daily.

Application:

Use KEMCOT-LG is usually used diluted with water in a concentration 10 % in water. The clean aluminum parts are immersed in the KEMCOT-LG bath at room temperatures of about 3 minutes to 5 minutes depending on the aluminum alloy and the condition of the solution. For spray operations the contact time is 1-2 minutes.

After treatment the parts should be thoroughly rinsed with water. First in water at ambient temperature and then with deionized water.

The final dry-off may be accomplished by conventional methods; however, temperature during drying should not exceed 50oC.

Usage:

The conversion coating on aluminum does not contain hexavalent chromium but trivalent chromium and is used where hexavalent chromium is not permitted.

Composition of Green coating:

CrPO4 • 6H2 O 75-90 %

Al2 O3 •3H2O 10-25 %