| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a polycarbonate diol of which color tone does not deteriorate even when heated, of which both molecular weight and composition exhibit small changes, and which is useful as a polyurethane having a high hardness, a high elastic modulus, wear resistance and an excellent heat stability.SOLUTION: A polycarbonate diol having a number average molecular weight of 250 or more and 5500 or less, and comprising structural unit derived from dihydroxy compound having moiety represented by the following formula (1), characterized to further contain at least one selected from the group consisting of orthophosphoric acid, phosphorous acid, phosphoric acid ester and phosphorous acid ester, and the total content of orthophosphoric acid, phosphorous acid, phosphoric acid ester and phosphorous acid ester relative to the total content of the metal element derived from transesterification catalyst is at a specific value or less.</p> |
