Bicomponent fiber and yarn comprising same
View Patent ↗The invention provides a bicomponent staple fiber comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate) wherein the bicomponent fiber has a substantially oval cross-section shape having an aspect ratio A:B of about 2:1 to about 5:1 wherein A is a fiber cross-section major axis length and B is a fiber cross-section minor axis length, a polymer interface substantially perpendicular to the major axis, a cross-section configuration selected from the group consisting of side-by-side and eccentric sheath-core, a tenacity at 10% elongation of about 1.1 cN/dtex to about 3.5 cN/dtex, a free-fiber length retention of about 40% to about 85%, and a tow crimp development value of about 30 to 55%, and a spun yarn comprising the bicomponent staple fiber.
1. A bicomponent staple fiber comprising poly(ethylene terephthalate) and poly(trimethylene terephthalate), said bicomponent staple fiber having:
a) a substantially oval cross-section shape having an aspect ratio A:B of about 2:1 to about 5:1 wherein A is a fiber cross-section major axis length and B is a fiber cross-section minor axis length;
b) a polymer interface substantially perpendicular to the major axis;
C) a cross-section configuration selected from the group consisting of side-by-side and eccentric sheath-core;
d) a tenacity at 10% elongation of about 1.1 cN/dtex to about 3.5 cN/dtex;
e) a free fiber length retention of about 40% to about 85%, and
f) a tow crimp development value of about 30% to 55%.
2. The bicomponent staple fiber of claim 1 having a tenacity at break of about 3.6 cN/dtex to about 6.0 cN/dtex, wherein the aspect ratio A:B is about 2.6:1 to about 3.9:1.
3. The bicomponent staple fiber of claim 1 having a tenacity at 10% elongation of about 2.0 cN/dtex to about 3.5 cN/dtex.
4. The bicomponent staple fiber of claim 1 wherein the aspect ratio A:B is about 3.1:1 to about 3.9:1.