POLYESTER CONJUGATE FIBER FOR STRETCHABLE WOVEN OR KNITTED FABRIC

摘要

PROBLEM TO BE SOLVED: To obtain a polyester conjugate fiber for a stretchable woven or knitted fabric having a soft touch feeling with a fullness feeling and good in color development properties. SOLUTION: This polyester conjugate fiber is a fiber obtained by mutually conjugating two kinds of polyester components consisting essentially of polyethylene terephthalate and different in melt viscosity into a side-by-side type. The component on the side of a high melt viscosity is a polyester in which a sulfonate salt group-containing compound is copolymerized in an amount of 0.5-5 mol% based on the whole acid component and a dimer acid is copolymerized in an amount of 1-10 mol% based on the whole acid component. Furthermore, the alkali weight reduction rate of the whole fiber is 0.2-0.5 wt.%/min and the retention ratio of crimp recovery stress at the time of 20 wt.% alkali weight reduction ratio is >=90% based on that prior to the weight reduction.