Painting Plastics

Q. We have been molding white plastic parts for a customer for some time, and now he wants the same parts in several additional colors. We would prefer molding in white and then painting the parts in the other colors to avoid downtime on our molding machines. We have no painting facility, but will install one if necessary. What do you think? B.S.

A. As an industrial paint consultant, I think it’s a great idea! It is important to remember that the painted surface should have the same appearance, and chemical and physical properties as the surface of the molded part. Your local industrial paint supplier can help you choose the proper material.

You also will need to clean the parts to remove molding compound and other surface contaminants before painting, therefore the necessary pretreatment facility also must be considered.

Paints can be applied by several methods, and spraying is the most common. If you intend to paint a large number of parts, a conveyorized line rather than a batch line is desirable. As you know, your painting line must meet all environmental and health regulations.