Effect of azo dyes on polyester fabrics for alkaline discharge-resist printing

This work describes the synthesis of a series of disperse dyes obtained by disazotization of di- and tri- substituent aniline and coupling with N,N-dialkylanilines. The purified dyes were characterized by FTIR, 1H-NMR and UV. In addition, the feasibility of alkaline discharge-resist printing for polyester fabrics with the dyes is discussed. The results show that the discharge-resist printing fabrics' ΔE of acid is better than an alkaline condition and the evenness of alkaline is worse, but sharpness is generally good. On the other hand, the abrasion fastness of treated fabrics' is 3-4, washing fastness is 4-5, but alkaline condition merely reveals a 3-4 grade.