| 摘要 |
PROBLEM TO BE SOLVED: To provide a catalyst for producing polyester, capable of producing a polyester having a favorable hue, particularly a low b-value of the obtained polyester, a small content of diethylene glycol in the polyester and a low terminal carboxyl concentration of the polyester. SOLUTION: There is provided a polymerization catalyst for producing polyester, which is a catalyst for producing polyester and is obtained by reacting a titanium compound with a phosphorus compound, wherein the particle diameter of the catalyst for producing the polyester is not more than 10 μm. The catalyst can be produced in a solvent with a pH adjusted to not more than 4.1. COPYRIGHT: (C)2011,JPO&INPIT |
