Abstract
Dyeing cotton and polyamide fibers in supercritical carbon dioxide with modified reactive dyes and acid dye was investigated at the range of 353 K to 413 K and 10 MPa to 30 MPa. Modification of reactive and acid dyes was carried out for decreasing the ionic property using tetrabutylammoniumbromide as cationic compound. Dyeing of cotton fibers was successful with modified reactive dye at 413 K and 20 MPa. Pretreatment of cotton fibers and addition of cosolvent were effective to obtain the higher color depth. The color depth of dyed cotton fibers drastically increased over 393 K. It was considered that the reaction of cotton with modified reactive dyes was accelerated at 413 K. Nylon, wool and silk fibers were also dyed successfully with modified acid dye without any pretreatment of fibers at 373 K and 20 MPa. Cosolvent was needed to achieve the level dyeing and high color depth.
