Synthesis and evaluation of a series of trisazo hetero bi-functional reactive dyes for cotton

Three linear trisazo derivatives, of the type A-NN-M1-NN-M2-E, incorporating both a sulphatoethylsulphone and a monochlorotriazine reactive group were prepared and evaluated as reactive dyes for the exhaust dyeing of cotton. The products were generally strong chromophorically but were dull in shade. All three dyes displayed good build-up in the presence of reduced levels of salt and the measured migration indices were similar to those of some commercial dyes. Although the fixation efficiencies of two of the dyes were similar to those of the commercial controls, their higher E−F (exhaustion−fixation) values resulted in poor wash-off performance.