High Lightfastness Acid Dyes Synthesized from Corresponding Anthraquinone Chromophore Utilizing a Sulfonation Reaction Part 2: Dyeing Properties on Polyamide and m-Aramid Fibers and Fastness

This study aimed at investigating the dyeability of synthesized acid dyes on fine nylon and m-aramid and their light fastness. A sulfonic acid group was introduced into the corresponding hydrophobic dye, which has an anthraquinone structure, to allow dyeing capabilities through ionic bonding with the nylon and m-aramid. Dyeability on fine nylon and m-aramid was mainly evaluated by the UV-Vis absorbance at maximum absorption wavelength (λmax). As the dyeing temperature increased to 110°C, the exhaustion rate of synthesized acid dyes increased. The synthesized acid dyes showed higher adsorption rates when dyeing occurred at high temperature. For fine nylon, as the synthesized acid dye concentration increased, the K/S value increased to 2.5 % o.w.f. and remained at that level thereafter. The fastness of light, wash, rubbing, and perspiration of fine nylon fabric dyed at these optimum conditions had higher ratings than those of commercial acid dyes. Regarding m-aramid dyeing, the grade of light fastness was higher than that of the commercial basic dye.