POLYESTER FIBER AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide a polyester fiber capable of efficiently forming fibrillar superfine fiber having a sufficient length and capable of providing polyester fabric having excellent hand and feel. SOLUTION: This polyester fiber is a modified multilobed polyester fiber mentioned below and comes into use after forming fibrillar superfine fiber by subjecting the fiber to alkaline weight-reducing treatment: (a) having at least one kind of aromatic dicarboxylic acid components or their ester-forming derivatives and at least one kind of diols components; (b) including >=1 wt.% organic metal sulfonate of the formula: R-SO3M (wherein, R is a 3-30C alkyl, or a 7-40C aryl or alkylaryl; M is an alkali metal) and (c) having multilobed fiber cross section having 3-20 projection. Thus, the modified polyester fiber is adjusted so as to form fibrillar superfine fibers having 0.1-10μm diameter and >=10μm length by being subjected to alkaline weight-reducing treatment.