PRODUCTION OF URETHANE MOLDED PRODUCT FOR POLISHING PADDING AND URETHANE MOLDED PRODUCT FOR POLISHING PADDING

摘要

PROBLEM TO BE SOLVED: To obtain an urethane molded product for polishing padding where polishing padding obtained by slicing a molded product has excellent polishing characteristics and irregularity in the polishing characteristics is small by including two kinds of expanded hollow microspheres having different particle sizes from each other. SOLUTION: Expanded hollow microspheres C having a particle size of 10-50 μm and/or expanded hollow microspheres C having a particle size of 80-100 μm are premixed with an urethane prepolymer A having isocyanate end group and/or an active hydrogen-containing compound B. The formulation ratio of the expanded hollow microspheres C to the expanded hollow microspheres D is (1:0.5) to (1:2.0). The active hydrogen-containing compound B comprises a diamine-based compound B-1 alone or a mixture of the compound B-1 with a low-molecular diol having a molecular weight of 500-1,000.