METHOD OF APPLYING INSIDE OF LOW PRESSURE LOW TEMPERATURE METAL MOLD

摘要

A method comprises in-mold coating on a molded thermoset polyester glass fiber substrate an in-mold coating composition at a pressure of from about 25 to 50 p.s.i. and at a temperature not in excess of about 150° F. for from about 2 to 12 minutes, said in-mold coating composition comprising the reaction product of an unsaturated aliphatic fumarate polyester diol, a saturated polyester diol flexibilizer, a cross- linking aliphatic polyol having from 3 to 6 OH groups, a diisocyanate in an amount by weight sufficient to provide from about 50 to 120%, preferably from about 80 to 103%, of the stoichiometric amount of --NCO groups required to react with all of the active hydrogen atoms in the coating composition and an ethylenically unsaturated monomer sufficient to polymerize with and crosslink the unsaturated polyester in admixture with a free radical peroxide initiator, an accelerator for said peroxide initiator and a polyurethane tin catalyst.