| abstract |
(57) [Summary] [Structure] The copper phthalocyanine pigment, which exists exclusively in the β phase, is first wet-milled in an agitated ball mill at high energy density in an aqueous, preferably neutral to alkaline medium, and then In the case of isolating the ground base material suspension obtained directly or in the case of the intermediate, after taking the intermediate in an inert liquid, it is preferable to use a conventional solvent at an elevated temperature, preferably in the presence of an organic solvent. Upon finishing, the pigment dispersant of the formula (I) is added in a preferred embodiment before or during wet milling, during or after finishing or in both treatment stages mentioned above. The α-phase copper phthalocyanine pigment and the pigment preparation are produced economically from the β-phase copper phthalocyanine crude pigment without environmental pollution. |