The active groups are monochloro-s-triazine and vinyl sulfone heterobi-reactive dyes. The commodity categories are named differently, mainly including M type, B type, RR type, BF type, BH type (partial), etc. The recommended dyeing temperature is 60～80℃. Due to the synergistic effect of two different reactive groups, this type of dye has moderate reactivity and good water solubility, level dyeing properties and migration properties. It is suitable for dyeing with small bath ratios and is currently the fastest growing and most widely used among the dye dyes. The variety, of course, has the advantage of relatively low prices.
The disadvantage is that the reactivity of the two active groups is quite different, that is, the reactivity of the monochloro-s-triazinyl group is much lower than that of the vinyl sulfone group, and the former is likely to cause insufficient fixation and the latter due to the vinyl sulfone group. The covalent bond formed with the fiber is poor in alkali resistance and prone to hydrolysis and bond breaking, and the final color fixation rate is low.