Patent ID: 6537661
Filing Date: 2003-03-25
Classification: D01F,Y10T

Abstract:
Melt processable, bleach resistant durable fibers having an elastic recovery above 50% after an extension to 160% elongation and a stress relaxation below 50% after an extension to 150% for 30 minutes formed from a polyurethane elastomer comprised of(a) from 75 to 90% weight, basis the total of (a), (b) and (c), of a polydiene diol having up to about two terminal hydroxyl groups per molecule and a number average molecular weight between 1000 and 20,000, (b) from 9 to 25% weight, basis the total of (a), (b) and (c), of a diisocyanate, and (c) from 0.8 to 5% weight, basis the total of (a), (b) and (c), of a chain extender which is a low molecular weight aliphatic diol, or a mixture of the low molecular weight aliphatic diol and from 0.1 to 4.0 mol %, basis the total mixture, of a diamine, wherein the hard segment content of the polyurethane elastomer is in the range from about 10 to about 30% weight.