Process for preparing metal phthalocyanines

Claim 1

IN A PROCESS FOR PREPARING A METAL PHTHALOCYANINE, WHICH COMPRISES HEATING, AT PHTHALOCYANINE-FORMING TEMPERATURE, A REACTION MIXTURE CONTAINING AN ORGANIC PHTHALOCYANINE INTERMEDIATE OF THE CLASS CONSISTING OF CARBOCYCLIC AROMATIC ORTHO-DICARBOXYLIC ACIDS, THEIR ANHYDRIDES, ACID HALIDES, ESTERS, AMMONIUM SALTS, MONO- AND DIAMIDES, AMIDES AND IMINOMIDINES, THE CORRESPONDING ORTHO-CYANOCARBOXYLIC ACIDS AND THEIR ESTERS, AMIDES AND AMMONIUM SALTS, AND CORRESPONDING W,W''-POLYHALO-O-DIMETHYL AND W-POLYHALO-O-CYANOMETHYL CARBOCYCLIC AROMATIC COMPOUNDS; A NITROGEN DONOR OF THE CLASS CONSISTING OF UREA, BIURET, GUANIDINE, GUANIDYL-UREA, DICYANDIAMIDE AND CYANURIC ACID, AND A PHTHALOCYANINE-FORMING METAL-YIELDING REAGENT, IN THE PRESENCE OF A CATALYST PROMOTING PHTHALOCYANINE FORMATION IN AN INERT ORGANIC LIQUID DILUENT, THE IMPROVEMENT WHICH COMPRISES INCLUDING IN SAID REACTION MIXTURE AN AMOUNT NOT SUBSTANTIALLY LESS THAN 25% OF THE WEIGHT OF THE SAID ORGANIC PHTHALOCYANINE INTERMEDIATE, OF A PHOSPHORIC ACID SALT OF A MEMBER OF THE GROUP CONSISTING OF THE ALKALI METALS, ALKALINE EARTH METALS, AND AMMONIUM RADICAL.