COMPOSITION OF REACTIVE DYES AND METHOD OF DYEING OR PRINTING FIBROUS MATERIALS OR LEATHER

A fiber reactive dye composition which comprises (1) a reactive dye of the formula (I), and (2) at least one member selected from the group consisting of reactive dyes of the formulas (II) to (IV), the formulas being represented each in the free acid form as follows: (I) (II) nd Z'' are each -CH=CH2 or -CH2CH2Z1, -CH2CH2Z2 or -CH2CH2Z3, respectively, wherein Z1, Z2 and Z3 are each a group capable of being split by the action of an alkali, and Q is -SO2CH=CH2 located at o-, m- or p-position against the imino when the -SO2Z in the formula (I) is located at o-, m- or p-position against the imino, respectively, provided that the reactive dye of the formula (I) is one having -CH2CH2Z1 as Z when the fiber reactive dye composition comprises the reactive dye of the formula (III), exhibits superior dye performance such as build-up property, solubility and durable stability, and is useful for dyeing or printing fiber materials or leather in a yellow color excellent in various fastness properties.