| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyurethane sheet having good shock absorption property and recovering property, high mechanical strength, and low water absorbency.SOLUTION: The polyurethane sheet is a reaction product of a composition containing a dimer acid polyester polyol (A), a polyisocyanate (B), and a foaming agent (C), and has a self-skin layer. The component (A) is a reaction product of a dimer acid (a-1), a low-molecular diol (a-2), and a low-molecular triol (a-3), and a reaction molar ratio between the low-molecular diol (a-1) and the low-molecular triol (a-3) is from 80:20 to 95:5. The component (B) is an isocyanate group-terminus prepolymer obtained from a diphenylmethane diisocyanate (b-1) and a polypropylene glycol(b-2) with molecular weight of 400-700. In the foamed polyurethane sheet, an isocyanate index is 90-120. |
