| 摘要 |
PURPOSE:A roll material capable of providing a roll having a low dynamic heat build-up, excellent dimensional stability, and high reliability, comprising an isocyanao group-terminated urethane prepolymer and a polyurethane elastomer having a specified crosslinking density. CONSTITUTION:A roll material consisting mainly of (A) an isocyanato group- terminated urethane prepolymer prepared by reacting W1 pts.wt. polyol having a molecular weight (MW1) >=500 and an (average) hydroxyl group functionality (F1) of at least 2 with W2 pts.wt. organic polyisocyanate having an (average) isocyanate group functionality (F2) of at least 2 and (B) a polyurethane elastomer having a molecular weight (MW3) <=5,000 and an (average) hydroxyl group funtionality (F3) of at least 2.2 and a crosslinking density (CD) (determined by the equation (wherein MW2 is the MW of the organic polyisocyanate) of 0.85 minimum. |
