Symmetrical dioxazine compounds and their use as fiber-reactive dyes

Abstract

A dioxazine compound represented by the following formula (I) in the free acid form, ##STR1## wherein V is a direct linkage or ##STR2## in which R.sub.3 is hydrogen or unsubstituted or substituted alkyl, and X is a direct linkage or an aliphatic, araliphatic or aromatic bridging group, provided that X stands for the bridging group as defined hereinabove when V is ##STR3## Y is unsubstituted or substituted phenylene, or unsubstituted or substituted naphthylene, Z is --SO.sub.2 CH.dbd.CH.sub.2 or --SO.sub.2 CH.sub.2 CH.sub.2 Z.sub.1 in which Z.sub.1 is a group capable of being split by the action of an alkali, Q is sulfo, hydroxy, halo, alkoxy, unsubstituted or substituted phenoxy or unsubstituted or substituted amino, and R.sub.1 and R.sub.2 independently of one another are each hydrogen or unsubstituted or substituted alkyl, which is useful for dyeing or printing fiber materials to give a dyed or printed product of a blue color superior in fastness properties, particularly those such as chlorine fastness, with superior build-up property.