| abstract |
An object of the present invention is to provide a method for dyeing a fiber in supercritical carbon dioxide, which makes it possible to dye even a hydrophilic dye without complicating the dyeing process. In a method of dyeing a fiber dyed in supercritical carbon dioxide, a dye having an anionic group is modified beforehand to make it hydrophobic, and then subjected to a dyeing operation. Specifically, by modifying anionic groups such as sulfonic acid groups and carboxyl groups in advance to form organic ammonium salts or esters, the solubility in supercritical carbon dioxide while maintaining the basic skeleton of the dye is maintained. Can be improved. Further, ultrasonic vibration is applied to the liquid in which the dye is dissolved or dispersed in the co-solvent, and then the liquid is introduced into the dyeing tank. [Selection diagram] Fig. 1 |