PREPARATION OF ULTRAFINE FIBER HAVING HIGH PHYSICAL PROPERTY

摘要

PURPOSE:To obtain the titled ultrafine fibers, useful for artificial leather, etc., and having a high strength, by drawing fibers, capable of being thinned, and containing a high-polymerization degree polyester having a specific intrinsic viscosity at a high draw ratio. CONSTITUTION:Fibers, e.g. island-in -sea type composite fibers, capable of being thinned into plural fibers by the thinning treatment, and containing a polyester having an intrinsic viscosity =0.75, preferably polyethylene terephthalate, are drawn at a draw ratio of preferably 3.3 or more to give a residual elongation =50%, preferably =40%, and the resultant fibers are then thinned, e.g. removal of the sea component by the dissolution, to give the amined fibers.