Amphiphilic acid dyes. Dyeing properties and interactions with surface-active systems

Sorption of Fluorinated Azo Dyes Containing Two Sulfonate Groups by a Nylon 6 Film.

“…Savarino et al investigated the effects of substituents on dyeing properties of a polyamide fiber using derivatives of 1-phenylazo-2-alkylamido-5-hydroxy-4-benzoic acid [6,7] and derivatives of 1. (2-alkylamido-4-hydroxyphenylazo)-4-benzenesulfonic acid [8]. They concluded that the dyes containing longer alkyl chains showed higher dye uptake due to their hydrophobicity.…”

“…As KL implies the electrostatic binding constant of the sulfonate anions with the positively charged amino end groups in the nylon 6 film, the charge density of the sulfonate anions affects the KL may be accompanied. The hydrophobicity is one of the most important factor in dye sorption by nylon [6][7][8].…”