Patent ID: 7195819

Claim:
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%.