POLYESTER POLYMERIZATION CATALYST, POLYESTER AND METHOD FOR PRODUCING POLYESTER

摘要

PROBLEM TO BE SOLVED: To provide a polyester polymerization catalyst comprising a component other than an antimony compound and a germanium compound as a principal component of the catalyst, having an excellent catalyst activity and providing a polyester having an excellent color tone when melt molded. SOLUTION: This polyester polymerization catalyst comprises at least one kind selected from aluminum and its compounds as a first metal-containing component. In the polyester polymerization catalyst, a color delta Lg value parameter (ΔLg) of a polyethylene terephthalate polymerized by using the catalyst determined from Hunter L and b values measured with a color difference meter satisfiesΔLg>-2.0 and a color delta bg value parameter (Δbg) thereof satisfiesΔbg<4.5.