COATING OF AUTOMOTIVE BODY

摘要

PURPOSE: To provide a coating method exhibiting good chipping resistance at a steel sheet as an outside of an automotive body and its underside part. CONSTITUTION: A microgel having 0.2-1.5μm grain size and a coating composition consisting of the following (A)-(C) are used, and after applying the coating, it is dried so that a gel ratio in the coated film of a chipping resistant coating material may be in a range of 70-100%. (A) is an epoxy resin containing hydroxy groups and having a number average mol.wt. of 500-5000 obtained by allowing an epoxy resin having hydroxy groups to react with a cyclic ester and/or a ring opening polymerization product of the cyclic ester, (B) is a polyester polyol resin containing the hydroxy groups and having the number average mol.wt. of 400-1000 and (C) is a polyisocyanate in which isocyanate groups are blocked.