NEW CELLULOSE ACETATE SLUB YARN AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain a new cellulose acetate slub yarn having randomly distributed thick parts and thin parts and a plurality of gentle ribbed swells on the fiber surface along the length, exhibiting mild spun silky luster and dry touch and resistant to the deterioration of the physical properties of the yarn. SOLUTION: A cellulose acetate slub yarn having thick parts is produced by carrying out dry spinning of a cellulose acetate fiber while intermittently and randomly lowering the take-up speed of the extruded yarn in a manner satisfying the formulas I and II. In the above process, the fiber is extruded and taken up under a condition satisfying the formulas III to V [V0 is take-up speed (m/min) at high-speed take-up mode; V1 is take-up speed (m/min) at low- speed take-up mode; Vj is linear extrusion velocity (m/min) of the spinning dope at the spinning nozzle; Vp is take-up speed (m/min)] to obtain the objective slub yarn having thick parts and thin parts randomly distributed in longitudinal direction of the yarn and a plurality of gentle ribbed swells on the fiber surface along the length.