Production of phthalocyanine colors in pigmentary state

Claim 1

A PROCESS OF PRODUCING AN AQUEOUS PASTE OF A PHTHALOCYANINE PIGMENT IN BETA FORM AND IN PIGMENTARY STATE, SAID PHTHALOCYANINE PIGMENT BEING A MEMBER OF THE GROUP CONSISTING OF COPPER PHTHALOCYANIE, NICKEL PHTHALOCYANIC, AND METAL-FREE PHTHALOCYANINE, WHICH COMPRISES FORMING A MIXTURE OF THE CRUDE PIGMENT, A WATER-SOLUBLE, ANIONIC DISPERSING AGENT, WATER, AND A POWDERED WATER-INSOLUBLE GRINDING AGENT, THE PARTICLES OF THE GRINDING AGENT BEING PREDOMINANTLY OF A SIZE BETWEEN 100 AND 325 MESH (U.S. SIEVE SERIES), THE CRUDE PIGMENT BEING ESSENTIALLY IN BETA FORM AND IN AN INITIALLY FINE STATE OF SUBDIVISION, THE QUANTITY OF GRINDING AGENT BEING NOT LESS THAN 2.5 PARTS BY WEIGHT PER APART OF PIGMENT, AND THE QUANTITY OF WATER BEING SUFFICIENT TO FORM A VISCOUS, WORKABLE MASS, SUBJECTING THE MIXTURE TO MILLING UNDER CONDITIONS PRODUCING INTERNAL SHEAR BY SETTING UP HIGH VEIOCITY DIFFERENTIALS BETWEEN ADJACENT PARTICLES OF THE MASS BEING MILLED, AND RECOVERING THE PIGMENT FREE OF SAID GRINDING AGENT.