In-mold coating (IMC) is applied to compression molded sheet molding compound (SMC) exterior automotive or truck body panels as an environmentally friendly alternative to make the surface conductive for subsequent electrostatic painting operations. The coating is a thermosetting liquid that when injected onto the surface of the part cures and bonds to provide a smooth conductive surface. In order to optimize the IMC process, it is essential to predict the time available for flow, that is the time before the thermosetting reaction starts (inhibition time) as well as the time when the coating has enough structural integrity so that the mold can be opened without damaging the part surface (cure time). 

PIMC has excellent hardness (4H) and chemical, stain, and UV resistance as a primer or topcoat. The coating is applied manually or robotically at 3- to 6-mil thickness. It replicates the tool surface sufficiently to impart a smooth or textured surface. When the powder cures in the mold, it chemically reacts with the SMC and seals the pores.