Compounds of formula (I) wherein R1 is hydrogen, hydroxy, halogen, nitro, cyano, amino, carboxy, carboxylic ester, sulfo, sulfonic ester, carboxylic amide, sulfonic amide, alkylthio, arylthio, alkoxy or aryloxy, R'1 is hydrogen, hydroxy, halogen, nitro, cyano, amino, carboxy, carboxylic ester, sulfo, sulfonic ester, carboxylic amide, sulfonic arnide, alkylthio, arylthio, alkoxy or aryloxy, X is -O-, -S-, -NH- or -N(alkyl)-, X' is -0-, -S-, -NH- or -N(alkyl)-, Y is hydrogen or carboxylic ester, Y' is hydrogen or carboxylic ester, Z is =C- or =N-, Z' is =C- or =N-, x is 0 or 1, when Z is =N-, then x is 0, y is 0 or 1, when Z' is =N-, then y is 0, A is a conjugated linking bridge of the formulae (II), (III), (IV), (V), or (VI), wherein n is 0, 1, 2 or 3, m is 0, 1, 2 or 3, B is a phenyl ring, T is =C(R3)- or =N-, wherein R3 is hydrogen, C1-C12alkyl or CN, W is a heterocyclic, or linear or polycondensed aromatic group which is unsubstituted or substituted by alkyl, halogen, hydroxy, alkoxy, alkylthio or amino, G is -CH= or -N=, and R2 is hydrogen, alkyl, halogen, hydroxy, alkoxy, alkylthio or amino, their preparation and their use in the production of coloured plastics or polymeric color particles.