BULKY YARN HAVING HIGH SHRINKAGE AND PRODUCTION THEREOF

摘要

PURPOSE:To obtain the title bulky yarn expressing high shrinkage and bulkiness free from twist torque in sudden water boiling treatment, by subjecting an undrawn yarn consisting of thermoplastic synthetic filament and having high orientation to false twisting by twisting and untwisting while drawing at specific temperature. CONSTITUTION:Undrawn yarn or imperfectly drawn yarn having high orientation and consisting of thermoplastic synthetic filament (preferably polyethylene terephthalate) is subjected to false twisting by twisting and untwisting while drawing at set temperature which is not higher than glass transition point to provide the aimed bulky yarn having =5% stretch recovery ratio, =25% shrinkage in sudden water boiling treatment, characteristics expressing bulkiness substantially having no twist torque, preferably =20% deformation ratio DELTAF of bulky yarn and =50% remain elongation after sudden wet-heat treatment.