METHOD OF DYEING WOOL, SILK OR THEIR MIXTURE (FIBER/YARN/KNIT FABRIC) WITH INDIGO

摘要

PROBLEM TO BE SOLVED: To provide a novel method of dyeing wool, silk or their mixture with indigo in a conventional dyeing machine.SOLUTION: A pretreatment method for causing wool, silk or their mixture to be acceptable for a subsequent indigo dyeing step includes a cationization step of imparting a cationic charge to generate another dye bonding site. A pretreatment bath for the pretreatment contains 3-80 gpl of a compound for cationization, e.g. chloride 3-chloro-2-hydroxypropyl trimethyl ammonium, and 3-25 gpl of sodium hydroxide. The pretreatment step is carried out for 5-30 s, and then, aeration is carried out for 30-180 s.