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  for Metal Finishing since 1989
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Clear coating on anodized aluminum with photographic image

2003

Hi,

I'm a photographer and am producing a series of prints using an industrial printing process called CTP. Essentially, this allows me to use a CO2 laser to remove a layer carbon from an anodized aluminum plate. Normally, this plate would then be used on an offset press but I'm actually presenting the aluminum plates themselves as fine art. My question is this: I want to coat the aluminum so that they'll have added UV protection and resist oxidization, scratches, etc. What are some options for finishing? Powder coating? Acrylic lacquer? Remember, I need to see the image below the coating and I need to last a long, long time (100+ years). Where in the NE (NY area preferred) can I deliver the plates for such a job?

Thanks in advance!

Howard Pyle
- Brooklyn, New York

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Hi,

If you really mean such a long time as 100+ years I would doubt there is anything you can put as a layer that will protect aluminum and last enough without degradation. Only thing that comes to my mind (if you are using laser) why don't you use a very hard an inert material such as glass instead of aluminum? Other alternatives less obvious and probably limited for other reasons can be granite, some marbles, gold, etc. In my opinion, not even bronze or stainless steel can equal to those in inertness and durability.

Bye,

Guillermo Marrufo
Monterrey, NL, Mexico
2003

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2003

I believe I know what you are doing here. I'm a bit of an art fanatic myself when it comes to aluminum. You are laser engraving into the part, correct? Standard anodizing overtop this finish in a clear anodize coating will suffice. Powdercoating would also, but the fact that as time goes on, both will fail in a yet to be determined time period. With the anodize finish you should be able to remove it, and not destroy the "picture" in the part, and subsequently re-anodize the part later down the road. Where with powder coating it either has to be burned off the surface, or sand/bead blasted off, thereby more than likely rendering your surface design to the same thing.

If you get 100 years w/o any loss of performance then it'd have to be an ultra tight controlled environment, and thats something you cannot do for anything less than billions of dollars I'm sure.

My suggestion is, expect 10-25 years reasonable in an internal environment w/o much humidity changes and moisture elements coming into contact with the part. If its for external environmental exposure, be happy with whatever you get from it, and thats just my feelings on it. 5-10 years exposed to most environments I would say is a very good period of time. There is far too many variables to say with outside use as basically there is no way of telling how many types of environments this part(s) can/could be exposed to.

Matthew Stiltner
plating company - Toledo, Ohio