Hydroxygallium phthalocyanine compound, production process therefor and electrophotographic photosensitive member using the compound

摘要

An electrophotographic photosensitive member having a high sensitivity to long-wavelength light as emitted by a semiconductor laser and causing little change in potential change during repetitive use is formed by using as a charge-generating material a hydroxygallium phthalocyanine having a crystal form characterized by a strongest peak at a Bragg angle (2&thetas; +/- 0.2 deg.) of 28.1 deg. in a CuK alpha characteristic X-ray diffraction pattern. The hydroxygallium phthalocyanine may preferably be produced through a process including treating a halogenated gallium phthalocyanine for conversion into a hydrous hydroxygallium phthalocyanine, freeze-drying the hydrous hydroxygallium phthalocyanine into a low-crystallinity hydroxygallium phthalocyanine, and milling the low-crystallinity hydroxygallium phthalocyanine.