Ricoh Company, Ltd.

Kazuo Nojima

Yasuo Hirano

Junji Kurokawa

Toshio Nakahara

Masako Chiba

Koji Suzuki

Nobuo Takami

Noboru Sawayama

Kazuyuki Sugihara

Naoki Iwata

Shigekazu Enoki

Yuichi Ueno

Jun Aoto

Takayuki Maruta

Norimasa Sohmiya

Hideaki Ema

Motoi Orihara

Fuchio Takeda

Hiroshi Takashima

Takuji Yoneda

Katsuji Watabe

Kaoru Yoshimatsu

Masaki Sekizawa

Yasutaka Nakamura

A member for developing electrostatic latent images to visible images is disclosed, which comprises a support, a first coating layer comprising an elastic material formed on the support, and a second coating layer comprising a flexible resin formed on the first coating layer.

Member for developing electrostatic latent images

An electrophotographic image forming apparatus using a charge roller for uniformly charging the surface of a photoconductive element, or image carrier, during image formation, and a charging device having the charge roller. The charging efficiency is enhanced, and a uniform charge distribution is set up by the application of a DC voltage only. This suppresses the increase in the cost of an apparatus, the increase in power source cost, and the generation of a great amount of ozone. As a result, a charging member and a photoconductive element are prevented from being deteriorated while environmental pollution is eliminated.

Image forming apparatus and charging device thereof

In a charging device included in an image forming apparatus for charging an image carrier uniformly, a charge roller has an elastic layer and a surface layer. The elastic layer is made of a substance having a medium electric resistance and having no conductive particles dispersed therein. The surface layer is made of a non-adhering substance having a greater non-adhering property than the substance constituting the elastic layer.

Charge roller for an image forming apparatus

A charging member is provided comprising an electroconductive substrate having sequential overlying layers of an elastic material comprising an epichlorohydrin rubber and a surface layer comprising an aqueous polyurethane resin. The resulting composite charging member represses adhesion of toner particles and dirt to the surface thereof, exhibits improved durability, and prevents lowering of the charging potential in a low temperature, low humidity environment.

Image forming apparatus charging member formed of sequential overlying

A method of developing latent electrostatic images and a developer-bearing member for use in the method are disclosed, which method includes the steps of (a) forming numerous micro closed electric fields near the surface of a rotatable developer-bearing member which comprises an electroconductive support and a surface layer formed thereon comprising an electroconductive organic polymeric matrix and numerous minute charge-retainable insulating segments distributed at least one the surface of the surface layer, by electrically charging the surface of the charge-retainable insulating segments; (b) supplying a one-component type developer comprising toner particles to the rotatable developer-bearing member to hold the developer on the rotatable developer-bearing member to hold the developer on the rotatable developer-bearing member by the numerous micro closed electric fields; and (c) bringing the rotatable developer-bearing member near or into contact with a latent-electrostatic-image-bearing member which bears a latent electrostatic image to develop the latent electrostatic image with the one-component developer to a visible toner image.

Method of developing latent electrostatic images and developer-bearing

Image forming apparatus which maintains a temperature of a charge roller

A charge roller rotatable in contact with a photoconductive element in the form of a drum or a belt and applied with a voltage for charging the element, and an image forming apparatus using the same. The surface of the charge roller is ground in order to remove toner particles and other impurities firmly deposited thereon, as needed. The charge roller is capable of uniformly charging the photoconductive element at all times.

Charge roller and image forming apparatus using the same

An image forming apparatus including a charge roller for providing a charge to a photoconductive member. The charge roller includes a metallic core with a conductive elastic layer covering the metallic core and a surface layer covering the elastic layer. The conductive elastic layer is preferably formed of an epichlorohydrein rubber or a urethane rubber. In addition, the conductive elastic layer and surface layer preferably have thickness and roughness characteristics as discussed herein.

Charge rollers having improved layer structure and/or surface

A developing device for image forming equipment capable of agitating and mixing a fresh toner and a developer sufficiently is disclosed. The device eliminates a change in image density among individual copies, irregularity in density corresponding to the spiral pitch of, for example, a toner transport screw, and irregularity in density in the front-and-rear direction (axial direction of a developing sleeve) ascribable to defective agitation. To replace or clean a desire part or parts built in a developing device, the device is divided into two such that the desired parts are freely accessible. This facilitates the cleaning and replacement of such parts.

Developing device for image forming equipment

A member for developing electrostatic latent images to visible images of a support having a first coating layer of an elastic material formed on the support, and a second coating layer of a flexible resin formed on the first coating layer, both coating layers having a volume resistivity of 10.sup.6 -10.sup.11 .OMEGA..cm. Such member is used in an apparatus in conjunction with a developer holding device, a developer supplying system, and a developer regulating element for regulating the thickness of the developer.

A developer carrier is used in a dry-type image developing device employing a one-component developer in an electrophotographic copier or an electrostatic recording apparatus. The developer carrier has a resin coating layer including an electrically conductive filler dispersed therein which is made of a material having a volume resistivity of at most 100 .OMEGA.cm. With this arrangement, the range in which the resistance of the surface layer varies under the ambient condition of varying temperature and humidity is small, producing a copy of stable image quality free from a smeared or contaminated background.

Developer carrier containing electrically conductive filler present in a

This invention relates to a developing apparatus for one component type toner, which has a thin film-forming element applying a thin film of one component type toner on the surface of a toner holder, characterized in that said thin film-forming element is composed of a silicone rubber comprising 100 parts by weight of a siloxane polymer having a cross linking density of 4-8.times.10.sup.-4 mol/cc and 30-70 parts by weight of silica.

Developing apparatus

A fixing roll characterized by crosslinking its surface with a rubber compound consisting essentially of a methyl vinyl system silicone raw rubber and silica and forming thereon a silicone rubber layer having a crosslinking density of 1.times.10.sup.-4 .about.8.times.10.sup.-4.

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Chiba, Japan

Kazuo Nojima