Color fast synthetic textile fibers from vinyl lactam polymer-containing acrylonitrile polymers

Claim 1

PROCESS OF RENDERING COLOR-FAST A DYED SYNTHETIC TEXTILE FIBER THAT IS COMPRISED OF (A) A FIBER OF AN INTIMATE ALLOY COMPOSITION OF (1) A FIBER-FORMING ACRYLONITRILE POLYMER THAT CONTAINS IN THE POLYMER MOLECULE ABOUT 85 WEIGHT PERCENT OF ACRYLONITRILE AND (2) A MINOR PROPORTION OF UP TO ABOUT 20 WEIGHT PERCENT, BASED ON THE WEIGHT OF THE DRY FIBER, OF A VINYL LACTAM POLYMER, SAID FIBER BEING COLORED WITH (B) A DYESTUFF ATTACHED THERETO SELECTED FROM THE GROUP OF DYESTUFFS CONSISTING OF DIRECT, ACID AND CHROME TYPES OF DYES, WHICH PROCESS COMPRISES TREATING SAID DYED FIBER, FOR AT LEAST ABOUT HALF AN HOUR AT A TEMPERATURE OF FROM ABOUT 70*C. TO THE BOIL WITH AN AQUEOUS TREATING SOLUTION AT A BATH-TO-FIBER WEIGHT RATIO BETWEEN ABOUT 5:1 AND 100:1, RESPECTIVELY, SAID TREATING SOLUTION CONTAINING (A) AN AMOUNT OF CUPRIC COPPER ION EQUIVALENT TO THAT WHICH IS OBTAINED WITH BETWEEN ABOUT 0.5 AND 8 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE FIBER, OF COPPER SULFATE (CUSO4), AND (B) AN AMOUNT OF A REDUCING AGENT FOR CUPRIC COPPER IONS THAT IS EQUIVALENT IN ACTIVITY TO AN AQUEOUS SOLUTION OF FROM 0.5 TO 8 PERCENT BY WEIGHT, BASED ON THE WEIGHT OF THE FIBER, OF HYDROXYL AMINE SULFATE TO RENDER FAST-TO-LIGHT THE COLOR IN SAID DYED FIBER.