Ask the Expert Question-and-Answer Archive

by Ron Joseph

June, 2004

Paint Adhesion Failure on Lexan Polycarbonate

Q. We are trying to prime a Lexan F60011-701 Polycarbonate vacuum formed part. The Mil-P-85582 Type I, Class C2 primer is not adhering to the part. Do you know of any primer that will meet the Mil spec or any process/pre-clean material that will make the polycarbate accept the primer?

A. Thank you for your e-mail. Unfortunately, without knowing more about the polycarbonate and the type of adhesion failure you are experiencing I can't help you further. You might need to speak to technical representatives of the paint supplier and/or the supplier of the polycarbonate. In most cases service preparation comprises thorough degreasing but in your case and adhesion promoter may also be necessary. Have you tried using epoxy primer MIL-P-MIL-P-53022?

If, after contacting your paint and plastics suppliers you still cannot solve your problem please feel free to contact me again and I will try to explore additional pressures for you.

Best wishes,

Ron Joseph