FIXING AGENT FOR IMPROVING FASTNESS PROPERTIES OF DYEINGS ON POLYAMIDE FIBERS AND PREPARATION THEREOF

摘要

ABSTRACT OF THE DISCLOSUREA fixing agent for improving the fastnessproperties of dyeings on polyamide fibers being a newcondensation product of 4,4'-dihydroxydiphenylsulfone, 4,4' -dihydroxydiphenysulfonesulfonic acid and a lower aliphaticaldehyde, which has a mean molecular weight of about 5,000 toabout 30,000 and a ratio of carbon atom content andsulfur atom content of 3 0 : 1 to 4 8 1, or its metalsalt, and when polyamide fibers are treated with thecondensation product or its metal salt, or the condensationproduct in the presence of a salt of metal, at a temper-ature of 95° to 120°C., the fastness properties, especiallywet-fastness properties of dyeings on polyamide fibersare remarkably improved.