To obtain a red reactive dye improved in dyeing properties, reproducibility and dyeing rate at a low salt concentration in dyeing treatment of a cellulose fiber material and excellent in chlorine resistance and sweat resistance.
A bisazo compound or a salt thereof is represented by formula (I) [wherein (m) and (n) are each 0 or 1, R1-R3 are each H atom or an alkyl group which can be substituted, D is phenyl or naphthyl which is substituted with one SO2CH=CH2 or SO2CH2CH2Z2, herein phenyl or naphthyl may be substituted with 1-2 substituents. B is a group represented by formula (II) or (III) (wherein U is a phenylene or naphthylene bonding group, X is a phenylamino group, Y is a halogeno group, a * mark is a bond bound to the azo group, and (p) and (q) are each 0 or 1)].
TOISHI KOJI
Toru Nakayama
Masayuki Enomoto