Bisazomethine pigments

None of the many mono- or bisazomethine pigments described in the literature, e.g. have gained commercial importance, mainly because of their insufficient resistance to solvents and migration, low colour strength or for economic reasons. 

Yet another type of polycyclic azomethine isoindolinones, where the isoindolinone benzene ring is either linearly or angularly fused with other benzene rings, have also been reported. Yellow to orange bisazomethine pigments of structure 20 were synthesized from the corresponding naphthalene dicarboxylic acids and diamines in the presence of phosphorous pentachloride. ... 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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