Copper phthalocyanine pigment systems
AssigneeCiba-Geigy Corporation
InventorCalvin C. Wanser
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Abstract
Copper phthalocyanine pigment systems with improved rheological and optical performance characteristics comprising copper phthalocyanine or halogen-substituted copper phthalocyanines blended with sulfonated copper phthalocyanine and provided with an anionic-cationic surfactant coating, and a process for the preparation thereof.
Claims9
A metal phthalocyanine pigment system consisting essentially of a blend of an unsubstituted metal phthalocyanine or a halogen nuclear-substituted metal phthalocyanine with a sulfonated copper phthalocyanine of the formula CuPc(SO.sub.3 H).sub.n wherein n is 1 to 4, coated with a combination of anionic and cationic surfactants, said sulfonated copper phthalocyanine being present in sufficient amount to provide said pigment with a 0.1-2.0%, by weight, sulfonic acid content, said anionic surfactant being present in a concentration of 0.008 to 0.035 parts by weight, per part of pigment and said cationic surfactant being present in a concentration of 0.06 to 0.27 parts per part of pigment.
A process for producing a coated metal phthalocyanine pigment the steps of (a) intimately contacting a crude unsubstituted or halogen nuclear substituted metal phthalocyanine with concentrated sulfuric acid until a pasty mass is formed;
- (b) pressing said mass and then reslurrying the presscake with water;
- (c) neutralizing said slurry by the addition of a base;
- (d) emulsifying the slurry with an organic solvent-water emulsion;
- (e) milling the emulsified slurry and exposing the milled material to elevated temperatures;
- (f) adding sulfonated copper phthalocyanine thereto in an amount sufficient to yield a 0.1-2.0%, by weight, sulfonic acid content;
- (g) adding 0.008-0.035 parts, by weight, of anionic surfactant and 0.06-0.27 parts, by weight, of cationic surfactant per part of pigment;
- (h) insolubilizing said sulfonated copper phthalocyanine and said anionic surfactant;
- and (i) recovering the coated metal phthalocyanine pigment from the slurry.
Dependencies are inferred from the claim text.