Abstract: An electrophotographic photoreceptor including at least an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate and including at least a charge generation layer; a charge transport layer; and a protective layer including a filler, wherein the filler is dispersed in the protective layer so as to occupy an area of from 3 to 5% of a cross section of the protective layer; the filler has particle diameter distribution having a peak at a diameter of from 0.2 to 0.3 &mgr;m; and the particles of the filler having a particle diameter of not less than 0.3 &mgr;m occupies an area of from 10 to 30% of the area of all the filler in the cross section of the protective layer.

Abstract: The image formation apparatus comprises an image substrate, a rotating unit that rotates said image substrate, a bias applying unit which applies a charge bias to the image substrate, a development unit that supplies a toner onto the image substrate, and a cleaning blade that removes the material deposited on the image substrate. A deposit removal operation is performed at a predetermined time while no charge bias is applied. The deposit removal operation includes rotating the image substrate, supplying the toner to the image substrate to an extent that upcurve of the cleaning blade is not caused, and removing the deposited material.

Abstract: An image forming apparatus includes an image bearing member on which an electrostatic latent image is formed, the image bearing member including a protective layer on a surface thereof, a developing device configured to develop the electrostatic latent image with toner to which an external additive is added to form a toner image, and a toner replenishing device configured to contain the toner and to supply air to the toner to replenish the developing device with the toner.

Abstract: A toner replenishing device includes a toner conveyance path for connecting a toner storing device with a developing device, a toner conveying device for conveying the toner from the toner storing device to the developing device along the toner conveyance path, and an air supplying device connected to the toner conveyance path vie an air supply path for supplying the toner storing device with air from a bottom of the toner storing device so as to agitate the toner pooling in the toner storing device.

Abstract: The present invention is aimed at carrying out high-precision and stable image formation using a gray-level image forming technique. In carrying out image formation by a gray-level electrophotographic process, the relationship between the layer thickness Tp of the photosensitive layer on the photosensitive member and the exposure diameter Db of a light beam emitted onto the photosensitive member is defined as 2Tp <Db, so that the charge diffusion and electric field in the photosensitive layer on the photosensitive member can be small. The maximum exposure within the exposure diameter Db is set at a value that can sufficiently reduce the differential sensitivity of the photosensitive layer, where the exposure diameter Db of the light beam is the minimum diameter at 1/e2 with respect to the peak value of the exposure distribution obtained by integrating the energy distribution of the light beam with the exposure time.

Abstract: In an electrophotographic image forming apparatus, a photoconductive element includes a photoconductive film having a thickness of 15 .mu.m or below. A light beam having a diameter of 50 .mu.m or below optically forms a latent image on the photoconductive element. Toner is caused to deposit on a dot image in an amount 1.2 times greater than on an area image. This is successful to minimize the variation of image quality and to render dots inconspicuous. The method of forming toner images is also included.