Method of treating yarns and filaments and products produced thereby

Claim 1

THE CONTINUOUS METHOD FOR INCREASING THE TENACITY AND ELONGATION AND ELIMINATING THE HOT WATER SHRINKAGE OF DRY SPUN YARN OF ACRYLONITRILE POLYMERS CONTAINING A MAJOR PROPORTION OF ACRYLONITRILE AND AN ACRYLAMIDE SELECTED FROM THE GROUP CONSISTING OF ISOPROPYL ACRYLAMIDE AND N-METHYL METHACRYLAMIDE WHICH COMPRISES CONDUCTING THE YARN UNDER PREDETERMINED NON-STRETCHING TENSION TO A ROLL HEATED TO A TEMPERATURE OF 180*C., PASSING THE YARN FOR A FRACTION OF A SECOND BETWEEN SAID ROLL AND A SHOE SPACED THEREFROM AND HEATED TO A TEMEPERATURE OF 370*C. WHEREBY THE YARN WITHOUT BEING COMPRESSED IS HEATED UNTIL IT BECOMES STRETCHABLE, STRETCHING THE HEATED YARN 550 TO 850% AFTER IT LEAVES THE HEATED ROLL, CONDUCTING THE YARN TO A SECOND ROLL HEATED TO A TEMPERATURE OF 210*C. AND PASSING THE YARN FOR A FRACTION OF A SECOND BETWEEN SAID ROLL AND A SHOE SPACED THEREFROM AND HEATED TO A TEMPERATURE OF 320*C. WHEREBY THE YARN WITHOUT BEING COMPRESSED IS HEATED UNTIL IT BECOMES RELAXABLE, PERMITTING THE YARN TO RELAX BEFORE AND AFTER CONTACT WITH SAID SECOND HEATED ROLL TO AN AGGREGATE AMOUNT OF FROM 11 TO 20%, MAINTAINING UNIFORM TENSION ON THE YARN BETWEEN THE STRETCHING AND RELAXING STEPS BY PASSING THE YARN AROUND TWO SEPARATE NON-HEATED ROLLS AND WINDING THE RELAXED PORTION OF THE CONTINUOUS YARN ON A SUPPORT WITHOUT STRETCHING TENSION.