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Coloring of anodized aluminum

I am running aluminum anodizing plant and interested to get into the coloring of aluminum. I just want to know whether there is any impact on the lightfastness of the colors obtained by dyeing at room temperature and dyeing at a temperature of 55-60 degree C. Which temperature is good for coloring the anodized aluminum?

Leonson Chungath
- Kerala, India
2006

The lightfastness rating of the dyes and the quality of the seal will have far more to do with your final product that air drying vs oven drying. If you use a high temp seal the parts will dry very rapidly. Using an oil free air to blow down the parts will reduce water spotting.

James Watts
- Navarre, Florida
2006

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James, I think you misread his post. He was referring to dyeing at room temp, not drying. But, you are correct, the seal quality, and dye lightfastness will have more of an impact than dye temp. Although, I do believe that the dye is more readily absorbed into the pores at an elevated temperature, as opposed to ambient. So it may have an impact on lightfastness. Marc Green anodizer - Boise, Idaho 2006 You are correct, Mark. I did not read the post correctly. The dye tank should be run at the temperature, dye concentration and pH that the manufacturer recommends for the best dye job. Out of specification work just invites problems. James Watts - Navarre, Florida 2006

Thank you, Mr.Marc and Mr.James. The information is helpful for me.

Leonson Chungath
- Kerala, India
2006

The quality of the dyestuff is as much as important as the anodising, dyeing and sealing process. Not all dyestuffs have the same lightfastness values. You have too use a high lightfastness value dye.

Timur Ulucak
aluminum extrusions & finishing - Istanbul, Turkey
2006

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2007

Mr Leonson,
Can you suggest the name of those dyes you want to use for aluminium?
Regards.
Dhiren

Dhiren Patel
- Ahmedabad