COMPOSITION CAPABLE OF FORMING YELLOWING-FREE, LOW-HARDNESS POLYURETHANE ELASTOMER, AND METHOD FOR PRODUCING YELLOWING-FREE, LOW-HARDNESS POLYURETHANE ELASTOMER USING THE SAME

摘要

[PROBLEMS] To provide a thermosetting polyurethane elastomer which is free of yellowish, can achieve a low hardness and a breeding-free property without the need of using any plasticizer, and has low tack and little fluctuations in hardness in accordance with the change in temperature. [MEANS FOR SOLVING PROBLEMS] Disclosed is a composition capable of forming a yellowing-free, low-harness polyurethane elastomer, which contains no plasticizer and comprises (A) an isocyanate-terminal prepolymer and (B) a polyester polyol both shown below. (A) An isocyanate-terminal prepolymer: an isocyanate-terminal prepolymer produced through a step for reacting hexamethylene diisocyanate with a glycol having an alkyl group as a side chain and having a molecular weight of 500 or less. (B) A polyester polyol: a polyester polyol produced from trimethylolpropane, 3-methyl-1,5-pentanediol and adipic acid, having an average functional group number of 2.5 to 3.5 and a number average molecular weight of 800 to 5,000.