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Silkscreening and Anodizing an Aluminum Surface

Is there any reason why an epoxy based ink that is silkscreened on an aluminum anodized (Type II, Class II, black) enclosure should not adhere. Sometimes we receive anodized metalwork where the silkscreen can easily be removed. Sometimes there seems to be adequate adhesion but over time the silkscreen comes off for no known reason.

Kerri Marsh
- Canada
2007

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The better way to obtain perfect "adhesion" is to make the lettering part of the dyeing process before anodizing; then it won't come off with steel wool or sandpaper, Kerri. But short of that, you do need consistency in the sealing process so the epoxy can get consistent "tooth".

I don't have personal experience with the following, but suspect it would work for you to seal for half the recommended time in hot water, silk screen, then seal for the remainder of the time either in water or nickel acetate.

You need to rely on a shop which knows how to get consistent adhesion, or retain a consultant if you wish to own the process. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

Has the epoxy ink been cured properly? I recently received some gloss powder coated panels which had been silk screened. The silk screening easily scraped off by fingernail. I put them in the oven for 2 minutes at 200°C and that solved the problem.

Jon Bailes
Sound Box Creations - Hoddesdon, Hertfordshire, UK
2007