Illustrative examples of suitable organic materials of high molecular weight (having a molecular weight usually in the range of from 103 to 10'g/mol) which can be colored with the pigment compositions of this invention are vinyl polymers, for example polystyrene, poly-a-methylstyrene, poly-p-methylstyrene, poly-p-hydroxystyrene, poly-p-hydroxy- phenylstyrene, polymethyl methacrylate and polyacryla