Lactam-based pigments and the use thereof in the production of colored plastics or polymeric color particles

摘要

The present invention relates to novel pigments of formula (1), wherein R₁ is hydrogen or C₁–C₁₂alkyl, R₂ is hydrogen, —CN, —COO-aryl, —COO-heteroaryl, —CONH-aryl or —CONH-heteroaryl, and R₃ is the radical of a heteroaromatic compound of formula or R₂ and R₃ together form a radical of formula wherein R₄, R₅, R₆ and R₇ are defined herein and to a process for the preparation of those pigments, and to their use in the production of coloured plastics or polymeric colour particles.