Pigments Containing More than Two Azo Groups

Dyes and Pigments Containing More than Two Azo Groups 

As an example of strategy (a), the synthesis of C. I. Direct Black 38,48, may be represented as follows  

A few azo dyes containing four, five and six azo groups, referred to respectively as tetrakisazo, pentakisazo and hexakisazo dyes, are known although they are progressively less important commercially and, naturally, the synthetic strategies are more complex. Also, because of the 

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