Patent ID: 6767498
Filing Date: 2004-07-27
Classification: D01F,D04H

Abstract:
A method for producing microfilaments, comprising:extruding a plurality of multicomponent fibers having at least one polymer component comprising an elastomeric polymer and at least one polymer component comprising a non-elastomeric polymer, wherein said elastomeric polymer has a solubility parameter (&dgr;) sufficiently different from said non-elastomeric polymer so that said elastomeric component and said non-elastomeric component split upon thermal treatment; drawing said multicomponent fibers to plastically deform said non-elastomeric component and to attenuate said elastomeric component such that said elastomeric component is capable of elastically contracting upon release of adhesion to the non-elastomeric component; and thermally treating said drawn multicomponent fibers under conditions of low or substantially no tension to separate said multicomponent fibers to form a fiber bundle comprising a plurality of elastomeric microfilaments and a plurality of non-elastomeric microfilaments which are more bulked than said elastomeric microfilaments.