US Patent 7087299 Polyester fibers and false twist-textured yarn comprising same

Polyester fibers having an individual fiber thickness of 0.1 to 10 dtex are produced from a polyester polymer produced by polycondensing an aromatic dicarboxylate ester in the presence of a catalyst including a mixture of a Ti compound component (A) including at least one member selected from titanium alkoxides and reaction products of the titanium alkoxides with a specific type of carboxylic acids or anhydrides thereof, with a specific P compound component (B), and/or a reaction product of a Ti compound component (C) with a specific P compound component (D). The resultant fibers have a good color tone (a low b value) a stable drawing and false-twisting processability and exhibit excellent appearance and performance.