Process for improving the application properties of Pigment Yellow 83

摘要

A Pigment Yellow 83 having improved application properties is obtained when the as-coupled weakly acidic or neutral aqueous pigment suspension has added to it sulphite ions, preferably in the form of sulphur dioxide or of a soluble sulphite, bisulphite or disulphite, and the suspension is then heated, advantageously at 50 to 100 DEG C for half an hour to 2 hours. Even industrial-scale batches of the pigment are obtained in a purity which guarantees satisfactory solvent and migration fastness properties.