abstract |
A polyester having a good color tone, an excellent forming property and a high resistance to cohesion of foreign substance around a melt-spinning orifice when the polyester is melt-spun, is produced by polymerizing an aromatic difunctional carboxylic acid-alkyleneglycol ester and/or oligomer thereof in the presence of a catalyst including a reaction product of (A) a Ti compound component including a Ti compound (1) of formula (I) or a Ti compound (2) produced by reacting the Ti compound (1) with an aromatic difunctional carboxylic acid of the formula (III) or anhydride thereof, with (B) a P compound component selected from P compound (3) of the formula (III).[R1=C2-C10alkyl group; p=1-3, n=2-4, R2=substituted or unsubstituted C6-C20aryl or C1-C20 alkyl group, m=1 or 2, q=0 or 1, and m+q=1 or 2]. |