Patent GB-482387-A (GB)
Title: Improvements in the manufacture and production of dyestuffs of the phthalocyanine series
IPC: C09B47/067
Filed: 1936-11-13
Abstract: Phthalocyanines containing metal are manufactured by heating dinitriles of aromatic o-dicarboxylic acids, or compounds yielding such dinitriles, i.e. o-cyanoamides or o-cyanoaldoximes, in the presence of metals suitable for forming metal phthalocyamines, or compounds of such metals, under increased pressure and in the presence of organic diluents free from nitrogen and hydroxy groups, e.g. hydrocarbons, especially aliphatic hydrocarbon mixtures such as ligroin, cyclohexane, and aromatic hydrocarbons such as benzene, toluene and xylene, halogen hydrocarbons such as carbon tetrachloride, tetrachlorethane, higher alkyl halides and aromatic halogen hydrocarbons, e.g. monochlorobenzene and monochlorotoluenes, and also ethers and esters.  The boiling point of the diluent should preferably not substantially exceed 150 DEG  C., and may advantageously lie between 80 DEG  and 150 DEG  C.  The preferred pressures are 3-15 atmospheres, though lower or higher pressures, e.g. up to 25 atmospheres, may be employed.  The metals are preferably employed in a state of fine dispersion, whilst the metal compounds may be in the form of double compounds, e.g. with ammonia or organic bases.  In examples: (1) phthalodinitrile is heated in a pressure-tight vessel with magnesium powder and toluene, yielding magnesium phthalocyanine, which may be converted into metal-free phthalocyanine by dissolving it in sulphuric acid and pouring the solution on to ice; (2) the magnesium powder in (1) is replaced by zinc dust, aluminium powder, calcium powder, iron powder, nickel powder or copper powder; (3) phthalodinitrile is heated with cuprous chloride or its addition compound with pyridine in the presence of ligroin, cyclohexane, benzene, toluene, xylene or monochlorobenzene; (4) phthalodinitrile is heated with cuprous chloride and pyridine in various proportions, in the presence of monochlorobenzene; (5) phthalodinitrile is heated with sodium methylate or other alcoholate in the presence of toluene chlorobenzene or bromobenzene or a mixture of diluents, to produce sodium phthalocyanine which yields metal-free phthalocyanine on boiling with dilute hydrochloric acid; (6) phthalodinitrile is heated with zinc oxide and toluene; (7) phthalodinitrile is heated with lead oxide or lead cyanamide in the presence of toluene; (8) phthalodinitrile is heated with nickel carbonate, pyridine and toluene; the nickel carbonate may be replaced by other metal compounds, e.g. calcium oxide, cobalt pyridine chloride, hexammine chromic chloride or iron chloride; (9) phthalodinitrile is heated with mercury diphenyl and xylene, yielding mercury phthalocyanine which may be converted into metal-free phthalocyanine by dissolving in sulphuric acid and pouring into water; (10) 4-chlorophthalodinitrile is heated with cuprous chloride and ligroin; (11) o-cyanobenzamide is heated with monopyridinocuprous chloride (prepared by stirring pyridine into a suspension of cuprous chloride in cyclohexane), in the presence of cyclohexane; (12) 3 : 4-dicyanodiphenyl is heated with cuprous chloride and toluene; (13) 3 : 4-dicyanodiphenyl is heated with cuprous chloride, pyridine and chlorobenzene.