The invention relates to a dye of the general formula (I) where D is the residue of a diazo component; R1 is hydrogen, (C1-C6-alkyl, (C1-C4)-alkoxy, hydroxyl, halogen, —NHCHO, —NHCO(C1-C6)-alkyl, —NHCOaryl, —NHSO2(C1-C6)-alkyl or —NHSO2aryl; R2 is hydrogen, (C1-C6)-alkyl, (C1-C4)-alkoxy, phenoxy or halogen; R3 is hydrogen, (C1-C6)-alkyl, substituted (C1-C6)-alkyl, (C3-C4)-alkenyl or substituted (C3-C4)-alkenyl; or R2 and R3 combine to form the radical —C*H(CH3)CH2C(CH3)2—, where the carbon atom marked * is attached to the phenyl nucleus; R4 is hydrogen, (C1-C6)-alkyl or phenyl; R5 is vinyl or a group of the formula —CHR6COR7, where R6 is hydrogen, (C1-C6)-alkyl or phenyl; R7 is (C1-C6)-alkyl, substituted (C1-C6)-alkyl, phenyl or substituted phenyl; and X is C1-C5)-alkylene. The invention for relates to a process to prepare the dye and their use.