Patent ID: 6833226
Filing Date: 2004-12-21
Classification: G03G

Abstract:
An electrophotographic apparatus comprising:an electrophotographic photosensitive member around which charging means for charging said electrophotographic photosensitive member, exposure means for exposing said electrophotographic photosensitive member to light to form a latent image thereon, developing means for developing the latent image formed on said electrophotographic photosensitive member with toner to produce a toner image, and transfer means for transferring the toner image to a transfer medium are provided in this order; said electrophotographic apparatus being without charge elimination means between said transfer means and said charging means, wherein said electrophotographic photosensitive member comprises a support, a charge generation layer containing a phthalocyanine compound and a charge transport layer, and has a light-area dark attenuation rate A and a dark-area dark attenuation rate B both of which satisfy the following expression (1): 1.0&lE;light-area dark attenuation rate A/dark-area dark attenuation rate B&lE;1.7â€ƒâ€ƒ(1); â€ƒwhere A=(|a1âˆ’a2|)/a1B=(|b1âˆ’b2|)/b1â€ƒand where a1=the surface potential of said electrophotographic photosensitive member immediately after charging of said electrophotographic photosensitive member by said charging means during a second image-forming operation of a first image-forming process, in which said electrophotographic photosensitive member had been charged by said charging means, and given whole surface exposure by said exposure means during a first image-forming operation of the first image-forming process; a2=the surface potential of said electrophotographic photosensitive member after leaving said electrophotographic photosensitive member for one second in the dark immediately after charging of said electrophotographic photosensitive member during the second image-forming operation of the first image-forming process; b1=the surface potential of said electrophotographic photosensitive member immediately after charging of said electrophotographic photosensitive member by said charging means during a second image-forming operation of a second image-forming process, in which said electrophotographic photosensitive member had been charged by said charging means, and kept unexposed during a first image-forming operation of the second image-forming process; and b2=the surface potential of said electrophotographic photosensitive member after leaving said electrophotographic photosensitive member for one second in the dark immediately after charging of said electrophotographic photosensitive member during the second image-forming operation of the second image-forming process, and wherein the phthalocyanine compound is oxytitanium phthalocyanine having strong peaks at Bragg's angles (2&thgr;Â±0.2Â°) of 9.6Â° and 27.3Â° in CuK&agr; characteristic X-ray diffraction.