METHOD FOR PRODUCING HIGHLY CRIMPY POLYESTER-BASED COMPOSITE YARN

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a highly crimpy polyester-based composite yarn having stable productivity and excellent crimp development by performing bicomponent spinning and drawing heat treatment of a side-by- side type composite yarn in which a high-viscosity component in the two components composing the composite yarn is an isophthalic acid copolyester and then carrying out relaxation heat treatment at a moderate overfeed ratio and temperature. SOLUTION: This method for producing the highly crimpy polyester-based composite yarn is characterized by comprising carrying out bicomponent spinning of the side-by-side type composite yarn in which the high-viscosity component in the two components composing the composite yarn is the polyester copolymerized with isophthalic acid, then performing drawing heat treatment and then carrying out the relaxation heat treatment by a noncontact heating in 5-25% overfeed ratio at 80-170 deg.C when producing the highly crimpy polyester- based composite yarn composed of two polyester components having different viscosities.