PRODUCTION OF MOLDED POLYURETHANE

摘要

PURPOSE:To obtain the subject molded article having high-density surface skin layer, exhibiting excellent discoloration resistance even in the absence of a protecting coating film and having excellent heat-resistance by using a specific hexamethylene diisocyanate polymer as an organic polyisocyanate. CONSTITUTION:The objective molded article is produced by the reaction of a composition consisting of (A) an organic polyisocyanate composed of a polymer of hexamethylene diisocyanate (abbreviated as HDI) containing >=10wt.% of a trimer of HDI forming an isocyanate ring, (B ) a polyol, (C) a foaming agent (e.g. water) and (D) a catalyst (e.g. tertiary amine) in inside of a mold. The component A is preferably produced by an isocyanulating reaction of HDI or an HDI polyol adduct at <=100 deg.C in the presence of a catalyst such as tertiary amine.