Preparation of novel crystal of hydroxygallium phthalocyanine and electrophotographic photoreceptor made using the same

PURPOSE: To prepare novel crystals of hydroxygallium phthalocyanine from which an electrophotographic photoreceptor high in sensitivity, good in durability and excellent in stability can be formed by treating hydroxygallium phthalocyanine with a first solvent, pulverizing it and treating it with a second solvent. CONSTITUTION: Hydroxygallium phthalocyanine is treated with a first solvent, mechanically pulverized, and then treated with a second solvent to prepare crystals of hydroxygallium phthalocyanine, the X-ray diffraction spectrum of which has strong peaks of diffraction at Bragg angles (2α±0.2°) of 7.5°, 9.9°, 12.5°, 16.3°, 18.6°, 25.1° and 28.3°. The first and second solvents may be ' the same or different from each other. Pref. examples of the first and second solvents include amides, esters, and ketones. The phthalocyanine compd., which has heretofore been proposed, is not sufficiently satisfactory in photosensitivity and durability when formed into a photoreceptor. By contrast, the above- mentioned crystals of hydroxygallium phthalocyanine is excellent in photosensitivity and durability. COPYRIGHT: (C)1993,JPO&Japio