Abstract: A manufacturing method for ceramic microspheres including the steps of; forming a suspension of ceramic fine powders as a dispersed phase and water as a dispersion medium; dispersing the suspension as droplets in a high boiling point liquid which has substantially the same specific gravity as the suspension and which is immiscible with water and nonreactive with the ceramic fine powder to make spherical particles; and subjecting the resultant product to drying and calcination.

Abstract: An electrophotographic method according to the present invention forms a color image on a photosensitive drum by repeating a cycle of charging, exposure and development for a plurality of times. The electrophotographic method comprises a step of applying a corona discharge component superposed with an AC voltage shifted to the negative or positive polarity which corresponds to that of the photosensitive drum to the photosensitive drum prior to the second image exposure so as to recharge the photosensitive drum.

Abstract: An electrophotographic device is provided with a photosensitive drum having a plurality of photosensitive layers which are different from one another in spectral sensitivity. First and second uniform exposure devices are adjacent to each other about the photosensitive drum. Each of the first and second uniform exposure devices includes a plurality of single color light sources. The light sources of the first exposure device have a different color than the light sources of the second exposure device. The colors correspond to the spectral sensitivity of each of the photosensitive layers, and are used as the uniform exposure light source for the photosensitive drum.

Abstract: Apparatus and method for applying developer to an image carrier in a copying machine so that a regulated amount of developer is applied to the image carrier during image development but is inhibited from reaching the image carrier during nondevelopment. The developer is supplied to a developer carrier roller. The amount of developer on the developer carrier roller is regulated by a regulating roller which is mounted in a position opposing the developer carrier roller. The developer carrier roller then carries the developer to a developing position opposite the image carrier. An electric field, which is reversible, is applied between the developer carrier roller and the regulating roller. During image development, the electric field is applied so that the developer is attracted to the developer carrier roller. During nondevelopment, the electric field is reversed and the developer is attracted to the regulating roller, thus inhibiting developer from reaching the image carrier.

Abstract: An electrophotographic method according to the present invention forms a color image on a photosensitive drum by repeating a cycle of charging, exposure and development for a plurality of times. The second charging process for charging the photosensitive drum having a first visible image thereon is performed to temporarily discharge a predetermined charge and thereafter limit reaching of the predetermined charge on a surface of the photosensitive drum in accordance with a surface potential at the photosensitive drum.

Abstract: An electrophotographic device is provided with a photosensitive drum having a plurality of photosensitive layers which are different from one another in spectral sensitivity. First and second uniform exposure devices are arranged at different positions about the photosensitive drum. Each of the first and second uniform exposure devices includes a plurality of single color light sources. The light sources of the first exposure device have a different color than the light sources of the second exposure device. The colors correspond to the spectral sensitivity of each of the photosensitive layers, and are used as the uniform exposure light source for the photosensitive drum.

Abstract: A developing apparatus is provided with a developing roller for carrying a toner thereon and an elastic blade pressed against the surface of the developing roller to apply the toner thereto. The toner is thus applied to the surface of the developing roller by the elastic blade to form a thin layer of the toner on the surface of the developing roller. The thin layer is opposed to a photosensitive drum at a predetermined space to deposit the toner on an electrostatic latent image on the photosensitive drum. Magnets and magnetic particles are provided to prevent the toner from leaking out.