Preparation of dyed plastics or polymeric dye particles

摘要

The present application relates to a process for preparing dyed plastics or polymeric dye particles characterized in that it comprises mixing a high molecular weight organic material with a coloristically effective amount of at least one dye of the formula where R₁ is hydrogen, hydroxyl or a radical -NHCO-R₆, where R₆ is C₁-C₆alkyl or unsubstituted or C₁-C₄alkyl- or halogen-substituted phenyl, R₂ is hydrogen, hydroxyl or a radical W-R₇, where W is -NHCO- or -S- and R₇ is C₁-C₆alkyl or unsubstituted or C₁-C₄alkyl- or halogen-substituted phenyl, R₃ is hydrogen, R₄ is hydrogen or hydroxyl, R₅ is hydrogen, or R₃ and R₄ combine to form the radical of the formula, where the rings A and B may independently bear further substituents.