| abstract |
A urethane resin solution capable of giving a urethane resin which exhibits a low stretch modulus, a low modulus of elasticity at low temperature, and excellent elastic recovery and is excellent in heat resistance and adhesiveness; a process for the production thereof; and a process for the production of a urethane resin. The urethane resin solution is produced by subjecting a mixture of an alkylene oxide and a lactone monomer to ring-opening polymerization with an initiator consisting of a polyoxy- tetramethylenediol having a molecular weight of 500 to 2500, if necessary, in the presence of a double metal cyanide complex catalyst to obtain a polyether ester diol having a molecular weight of 800 to 4000, reacting the polyether ester diol with a polyisocyanate to form an isocyanate-terminated prepolymer, and then reacting the prepolymer with a chain extender such as a low-molecular diamine and/or a low-molecular diol in an organic solvent. The obtained solution can give a urethane resin by molding into a prescribed shape or by application to a substrate by coating or immersion and solvent removal subsequent to the application. |