Powder In Mould Coating as a superior finishing solution for SMC in automotive applications

This paper describes the powder in mould coating process (PIMC) in combination with sheet moulding compound (SMC). A powder coating is applied to a preheated mould to pre-gel. SMC is placed into the mould and pressed as one with the PIMC to cure together inside the mould. When the SMC is removed from the mould it comes out coated with a highly durable, super smooth powder coating layer which has a strong adhesion to the SMC. The coating has good barrier properties, hardness, flexibility and abrasion resistance. With the unique controlled chemistry based on durable unsaturated polyester and vinylether urethane the coating properties and curing behavior can be fine tuned to automotive requirements. Rheological curing studies were conducted to investigate the curing behavior.