Painting Molded ABS
Q. I am the quality specialist for a first-tier supplier to the automotive industry. In one of our product lines, we injection-mold parts, then paint and assemble them in this facility. We are having a problem painting an ABS injection-molded part, with dark, cloud-like spots and long parallel splays. The defect is consistent in location on each molded part. Can you help? J.C.
A. Although I worked with plastics many years ago, my area of expertise is organic coatings, not injection molding. Since the paint defect is in the same spot on every part, I believe you have a molding and not a painting problem. On the other hand, surface defects are often telegraphed through a coating. In that case, the problem can be solved by increasing the paint film thickness.
An overview of spraying, dipping, flow coating, and everything in between.
Simply heating up the substrate does not cure the coating. There are many variables to consider when choosing the best cure oven for your application...
Better adhesion, enhanced corrosion and blister resistance, and reduced coating-part interactions make pretreatment a must.