Hard, Abrasion-Resistant Coating

Q. I have a contract to paint what we refer to as piano keys. These are plastic keys that hinge on the back to click on and off when pressed by a person’s finger. This customer’s previous painting contractor went out of business, and I have not been able to find out how the keys were painted before or what paint was used. The paint is very hard and cannot be scratched with a fingernail. The color is a cool gray on the pantone color scale. I have sent samples to four different paint suppliers and have bought different paints and primers, but none of them have given us the desired hardness and abrasion resistance. I have taken samples to silk screeners, auto body shops painters and other job shops. They all have been impressed with how tough the paint is, but I have found nobody who knows where to get such a paint. Do you have any idea what the coating is? —M.W.

A. Since the piano keys are made of plastic, that rules out most powder coatings except the low-temperature-curing types. Liquid coatings that have excellent hardness and abrasion resistance include phenolics, amine-cured epoxies, dicy-cured epoxies and polyamides.

I know that doesn’t answer your question, but perhaps one of our Painting Clinic readers can provide the answer.