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  for Metal Finishing since 1989
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Vacuum deposition on powders

Is it possible to vacuum metallize aluminum on powder pigments? Do you know of anyone that has done it? Thank you for your reply.

Saul Heiman
an ink company - La Jolla, California, USA
2003

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I know that there are people out there that vacuum coat powder. Usually it is for making catalysts. I don't know anyone who has coated pigment. Coating powder isn't easy. The biggest problem is how do you uniformly move the powder through the vacuum deposition area? The easiest way is to drop the powder through a coating area via gravity. This means you have to have a pretty high coating rate or a very long drop/coating zone to get the thicknesses you require. I've only heard of people doing these coatings with magnetron sputtering using either parallel magnetrons or inverted cylindrical magnetrons. There might be other methods but I haven't heard of them.

John Davis
- Berthoud, Colorado, USA
2003