Chromatising
Process Information
Chromatising
Guide for chromatising treatment including green, yellow chromium and colourless coating.
Green
chromium phosphate
This is general process for the pre-treatment of Aluminium. This bath contain Mixtures of phosphoric acids, chromic acids and additives. This process is more popular in the food industry as it is non toxic. This process forms excellent substrate for powder coatings. The coating formed is dark green in colour weighing 0.5-1.5 gm/m2, It gives limited corrosion resistance.
Yellow
chromium phosphate
This process is more popular in the powder coating industry. The bath contain mixture of chromic acid along with accelerators. This process gives dark yellow coloured (process applicable to OEMs) coating which is having high corrosion resistance. Since this process is based on hexavalent croium, it suffers from the disadvantages such as effluent problems etc.
Colourless coating
This process is more popular in the powder coating industry. The bath contain mixture of chromic acid along with accelerators. This process gives dark yellow coloured (process applicable to OEMs) coating which is having high corrosion resistance. Since this process is based on hexavalent croium, it suffers from the disadvantages such as effluent problems etc.