Granted Patent B2

US 6,974,628 · App. 11/006,253 · Granted Dec 13, 2005

Abstract

Claims (8)

1. A bicomponent fiber comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate) having a reduced crimp contraction value of about 6% to about 15%, wherein the fiber is derived from a precursor fiber having a developed crimp contraction value of about 20% to about 80%.

2. A bicomponent fiber comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate) having a restored crimp contraction value that is about 70% to about 100% of the precursor fiber's developed crimp contraction value.

3. The fiber of claim 1 , made by a continuous process for treating a bicomponent polyester fiber comprising the steps of:

a) providing a bicomponent fiber comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate) that has been heated to a first heat-treating temperature and cooled to a temperature below about 70° C.; wherein the fiber has an initial crimp, contraction value and a developed crimp contraction value;

b) applying tension to the fiber of about 0.001 to about 0.088 dN/tex;

c) heat-treating the tensioned fiber at a second heat-treating temperature that is no lower than about 75° C. and no higher than the first heat-treating temperature;

d) cooling the fiber to lower than the second heat-treating temperature;

e) releasing the tension from the fiber, wherein the resulting treated bicomponent fiber has a reduced crimp contraction value.

Assignments (8)