Low the hardness polyurethane constituent, elastomer and low hardness roll

摘要

PROBLEM TO BE SOLVED: To provide a thermosetting low hardness polyurethane whose permanent compression set is low and having good surface property, excellent in workability and has a JISA hardness of 10-40 without plasticizer, and to provide a polyurethane elastomer and a low hardness roll obtained from the same. SOLUTION: The thermosetting low hardness polyurethane whose permanent compression set is low, and having good surface property, excellent in workability and JISA hardness of 10-40 without plasticizer, is composed of the prepolymer terminal isocyanate groups which are obtained by reacting the (A) organic polyisocyanate and the (B) polyol whose number of average functional group is 4-6 and whose number average molecular weight is 1,000-10,000, and the polyalkylenepolyol whose number of average functional group is 4-6 and whose number average molecular weight is 4,000-150,000 as a curing agent. The polyurethane elastomer and the low hardness roll which is obtained from the same are provided.