| 摘要 |
PURPOSE: To obtain a toothed belt having sufficient softness and a little irregular rotation by using a polyurethane elastomer obtained by reacting a prepolymer, which is obtained by reacting an active hydrogen-containing compound to a polyisocyanate, to a mixture cross-linking agent of specified amine. CONSTITUTION: A small-size toothed belt is formed by embedding a core material in a main body having teeth arranged on the inner peripheral face at a fixed pitch. The small-size toothed belt consists of the main body made of a polyurethane elastomer which is obtained in such a manner that a prepolymer obtained by reacting an active hydrogen-containing compound having at least two functional groups having active hydrogen to a polyisocyanate is reacted to a cross-linking agent consisting of a mixture of 2,4-diethyl tolylenediamine to be expressed by a formula I and 2,6-diethyl tolylenediamine to be expressed by a formula II. |
