| 摘要 |
PURPOSE:To reduce change of physical properties due to temp. and to obtain superior durability by using a urethane rubber resulting from the reaction of polytetraethylene glycol specified in mol.wt. with polyisocyanate. CONSTITUTION:The urethane rubber used here is produced by reacting polytetramethylene glycol having an average mol.wt. of 500-6,000 with polyisocyanate. The polyurethane obtained by using polytetramethylene glycol as the starting material of polyol is small in change of repulsion elasticity and hardness due to temp. and superior in hydrolyzability. Workability is good and prevents broken foam marks and the like on the surface of a blade, thus permitting a cleaning blade superior in mechanical strength, small in its temp. dependence, and good in durability to be obtained. |
