Patent ID: 8506652

Claim:
Novel disperse azo dyes of formula (1) wherein, X, Y and Z are, independently, hydrogen, halogen, cyano, nitro or SO 2 F; Wherein at least one of X, Y and Z is SO 2 F. R 1 is hydrogen, methyl, hydroxyl or NHR 4 ; R 2 is hydrogen, chloro or methoxy; R 3 is hydrogen, (C 1 -C 4 )-alkyl or CH 2 (CH 2 ) n COOCH 2 CN; R 4 is —COCH 3 , —CO C 2 H 5 , —SO 2 CH 3 or SO 2 C 2 H 5 ; n and m are independently 0,1 or 2. with the proviso: When, Y and Z both are Cl, R 1 is other than methyl.