I have been contacted by a company to engrave phone covers, they are a soft plastic and hard plastic but one color. Do you have any suggestions as to what kind of paint to use for colorfill that won't easily come off. This could be the account I have been waiting for since I opened the business and I want to get it right. I haven't done a lot of color fill but what I have done the items weren't handled like a cell phone case would be. Does any one know if they make an epoxy paint that might work. If I can get this right I could be very happy and busy.