US 6,673,443 B2 · Polyester conjugate fiber pirn and method for producing same

Abstract

The present invention provides a polyester-based conjugate fiber pirn that is formed by winding, in a pirn shape, a conjugate fiber wherein the fiber is formed from a single filament prepared by combining two types of polyester components in a side-by-side manner or in an eccentric sheath-core manner, and at least one polyester component forming the single filament is a poly(trimethylene terephthalate) containing 90% by mole or more of trimethylene terephthalate repeating units, the winding amount of the conjugate fiber pirn being 1 kg or more, the winding angle in a taper portion thereof being from 15 to 21°, the winding hardness in the cylinder portion thereof being from 75 to 92, and the starting temperature of thermal shrinkage stress manifestation of the conjugate fiber being from 50 to 80° C.

Claims14

Dependent claims

A polyester-based conjugate fiber pirn characterized in that the polyester-based conjugate fiber pirn is formed by winding in a pirn shape that satisfies the conditions (1) to (4) mentioned below, a conjugate fiber wherein the fiber is formed from a single filament prepared by combining two types of polyester components in a side-by-side manner or in an eccentric sheath-core manner, and at least one polyester component forming the single filament is poly(trimethylene terephthalate) containing 90% by mole or more of trimethylene terephthalate repeating units:

(1) the winding amount of the conjugate fiber pirn 1 kg or more;
(2) the winding angle in a taper portion thereof is from 15 to 21;
(3) the winding hardness in the cylinder portion the eof is from 75 to 92;
and
(4) the starting temperature of thermal shrinkage stress manifestation of the conjugate fiber is from 50 to 80° C.

2 more elements

A method for producing a polyester-based conjugate fiber pirn, wherein two types of polyesters in which at least one type of polyester contains 90% by mole or more of trimethylene terephthalate repeating units are injected from a spinneret by melt spinning, the injected polyesters are cooled and solidified with cooling air, the solidified yarn is drawn, and a conjugate fiber formed from a single filament that is formed by combining the two types of polyesters in a side-by-side manner or in an eccentric sheath-core manner is wound in a pirn shape in an amount of 1 kg or more, the method satisfying the conditions (A) to (C) mentioned below:

(A) the tension of the yarn during drawing is from 0.10 to 0.35 cN/dtex;
(B) the relaxation ratio during winding the conjugate fiber in a pirn shape is from 2 to 5%;
and
(C) the conjugate fiber pirn is aged in an atmosphere at a temperature of from 25 to 45° C. for 10 days or more.

1 more element

Dependencies are inferred from the claim text.

Polyester conjugate fiber pirn and method for producing same

Life of this patent

Polyester conjugate fiber pirn and method for producing same

Life of this patent

Abstract

Claims14