Benzimidazolone manufacture

The chemistry and manufacture of the coupling components for yellow/orange and red benzimidazolone pigments are treated separately. 

Table 10-4 Known pigment brands and manufacturers of benzimidazolone pigments as of 1997). ...

Benzimidazolone pigments first appeared on the German market in 1964. The relative order in which the seventeen generic structures, still available as pigments from Clariant, were launched in Europe, is listed in Table 10.3. As mentioned above, there are numerous manufacturers of benzimidazolone pigments today. 

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