NEW MATERIAL: A compd. represented by formula I (R1 is H, methyl, or ethyl; X is H or hydroxysulfonyl; Hal is F or Cl; D is a phenylene group substd. by one or two phenylene, carboxyl, or hydroxysulfonyl groups or a naphthylene group substd. by one or two hydrosulfonyl groups; and A is a reactive group having hydroxyl and nitrogen groups and reactive only substitutionally with a substrate to be treated provided A and D may combine with each other to form a benzene-fused reactive group having hydroxyl and nitrogen groups and reactive only substitutionally with a substrate to be treated).

EXAMPLE: A compd. represented by formula II.

USE: A reactive dye for dyeing cellulose fibers in bluish red.

PROCESS: A diamine represented by formula III is diazotized and then coupled with a coupling component represented by formula IV.