| abstract |
(57) [Problem] To provide a polyester polymerization catalyst containing a component other than an antimony compound or a germanium compound as a main component and providing a polyester excellent in catalytic activity, heat stability, and hydrolysis resistance. A polymerization catalyst containing, as a metal-containing component, at least one selected from aluminum and a compound thereof, wherein a polyethylene terephthalate (PET) polymerized using the polyester polymerization catalyst has a hydrolysis resistance parameter (HS). , HS <0.10. It is preferable to use a specific phosphorus compound as an additive. |