SURFACE DYEING METHOD OF COTTON YARN FOR DENIM BY LOW TEMPERATURE DIP-DYELING, COTTON YARN FOR DENIM AND THE DYEING DEVICE

摘要

PURPOSE: A method for dyeing the surface of cotton yarn for denim by dip dyeing is provided to be applied to various clothes such as jacket, shirts, and blouse. CONSTITUTION: A method for dyeing the surface of cotton yarn comprises: a step of drying a bunch of cotton yarn for denim in a dyeing device; a step of inputting the bunch of cotton yarn in a dyeing bath; a step of adding diluted caustic soda(NaOH) into the dyeing bath; a step of uniformly contacting the caustic soda with the cotton yarn; a step of collecting the caustic soda form the dyeing bath; a step of supplying 2-10% of reduction dye through a circulation pump; a step of adding hydrosulfide(Na_2S_2O_4) reducing agent; and a step of dyeing the surface of the cotton yarn with the reducing dye.