Abstract: A reactive dye composition comprising a monoazo compound of the following formula (I) in the free acid form, ##STR1## and at least one member selected from monoazo compounds of the following formulas (II) to (IV) in each free acid form, ##STR2## wherein Z, Z' and Z'" are each --CH.dbd.CH.sub.2 or --CH.sub.2 CH.sub.2 Z.sub.1, --CH.sub.2 CH.sub.2 Z.sub.2 or --CH.sub.2 CH.sub.2 Z.sub.3, respetively, in which Z.sub.1, Z.sub.2 and Z.sub.3 are each a group capable of being split by the action of an alkali, Z" is --CH.dbd.CH.sub.2, and any one of X and Y is sulfo, and the other is hydrogen, exhibits superior dye performance such as solubility, storage stability and build-up property, and is useful for dyeing or printing fiber materials such as cellulose fiber in a red color excellent in various fastness properties.

Abstract: A monoazo compound represented by the following formula in a free acid form, ##STR1## wherein R is hydrogen or unsubstituted or substituted C.sub.1 to C.sub.4 alkyl, X is unsubstituted or substituted phentyl or naphthyl, Y is unsubstituted or substituted phenylene or 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 splittable group by the action of an alkali, and R.sub.1 and R.sub.2 are independently hydrogen or unsubstituted or substituted C.sub.1 to C.sub.4 alkyl, phenyl or benzyl, excepting the case where R.sub.1 and R.sub.2 are hydrogen, which is useful as reactive dyes of high solubility and good build-up property for giving dyed or printed products of a deep red color excellent in fastness properties.

Abstract: A monoazo compound of the following formula, ##STR1## wherein D is sulfonaphthyl, sulfophenyl or carboxyphenyl, any one of A.sub.1 and A.sub.2 is sulfo and the other is hydrogen, methoxy or ethoxy, R.sub.1 and R.sub.2 are independently hydrogen or alkyl, B.sub.1 and B.sub.2 are independently phenylene or naphthylene, and Y.sub.1 and Y.sub.2 are independently vinyl, .beta.-sulfatoethyl or the like, which is useful for dyeing or printing fiber materials to give dyed or printed products of a deep color excellent in fastness properties.

Abstract: A monoazo compound represented by the following formula in a free acid form, ##STR1## wherein D is a sulfophenyl or sulfonaphthyl, R.sub.1, R.sub.2 and R.sub.3 are independently hydrogen or alkyl; B.sub.1 and B.sub.2 are independently phenylene, naphthylene, or alkylene, provided that at least one of B.sub.1 and B.sub.2 is phenylene or naphthylene, Y.sub.1 and Y.sub.2 are independently vinyl or --CH.sub.2 CH.sub.2 Z in which Z is splittable by the action of an alkali, and n is 0 or 1, and the monoazo compound is useful for dyeing or printing fiber materials to obtain dyed or printed products of extremely deep scarlet color excellent in various fastness with superior build-up property.

Abstract: A monoazo compound of the following formula, ##STR1## wherein A is phenyl or naphthyl, B.sub.1 and B.sub.2 are each phenylene or naphthylene, R.sub.1 is hydrogen, halogeno, alkyl, alkoxy, ureido or acylamino, R.sub.2 is hydrogen or takes together with R.sub.1 to form benzene, R.sub.3 is hydrogen, alkyl, alkoxy or sulfo, R.sub.4 and R.sub.5 are each hydrogen or alkyl, and Y.sub.1 and Y.sub.2 are each vinyl, sulfatoethyl or the like, which is useful for dyeing hydroxyl group-containing and amide-containing fiber materials to obtain dyed products of excellent fastness properties with excellent build-up property and reproducibility of dyeing irrespective of changes in dyeing temperatures, bath ratio or salt concentration in some degree.

Abstract: A monoazo compound of the following formula in a free acid form, ##STR1## wherein R.sub.1 is alkyl, .beta.-carboxyethyl, .beta.-carboxyvinyl or phenyl, R.sub.2, R.sub.3 and R.sub.4 are each hydrogen or alkyl, A.sub.1 and A.sub.2 are each phenylene or naphthylene, B is ##STR2## in which R.sub.5 is hydrogen, methyl or sulfo, L is hydrogen or sulfo, and the asterisked linkage is bonded to the azo group, and Z.sub.1 and Z.sub.2 are each --SO.sub.2 CH.dbd.CH.sub.2, --SO.sub.2 CH.sub.2 CH.sub.2 OSO.sub.3 H or the like, which is useful for dyeing or printing fiber materials to give dyed or printed products of extremely deep red color excellent in various fastness properties and dischargeability.

Abstract: A monoazo compound of the following formula in a free acid form, ##STR1## wherein A.sub.1 and A.sub.2 are phenylene or naphthylene, Z.sub.1 and Z.sub.2 are --SO.sub.2 CH.dbd.CH.sub.2 or --SO.sub.2 CH.sub.2 CH.sub.2 Y in which Y is a splittable group, R.sub.1 and R.sub.2 are hydrogen or alkyl, and D is sulfophenyl or sulfonaphthyl, provided that --A.sub.1 --Z.sub.1 and --A.sub.2 --Z.sub.2 are different from each other when D is sulfophenyl and both R.sub.1 and R.sub.2 are hydrogen, which is useful for dyeing or printing fiber materials to give dyed products of high fastness properties with extremely high color depth.

Abstract: A monoazo compound of the following formula in a free acid form, ##STR1## wherein R.sub.1, R.sub.2 and R.sub.4 are independently hydrogen or lower alkyl, R.sub.3 is lower alkyl, acyl or (sulfo)- phenyl, R.sub.5 is hydrogen or sulfo, B is (sulfo)phenylene or sulfonaphthylmethylene, X is chlorine, fluorine, phenoxy or (substituted)amino, A is (substituted)phenylene or (substituted)naphthylene, and Z is --SO.sub.2 CH.dbd.CH.sub.2 or --SO.sub.2 CH.sub.2 CH.sub.2 Y in which Y is a splittable group by the action of an alkali, which meets requirements of high degree in a dye industry with respect to dyeing properties such as build-up property and fastness properties such as formalin fastness, formalin-light fastness.