Patent application number | Description | Published |
20100142998 | CHARGING ROLLER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS - The present invention provides a charging roller having a stable chargeability and capable of preventing occurrence of “fogging” on an electrophotographic image. The invention relates to a contact-charging type charging roller which includes a conductive support and a surface layer. The surface layer contains a binder, resin particles containing a carbon black dispersed in the binder, and graphitized particles dispersed in the binder; and the surface layer has, on its surface, convex portions derived from the resin particles, and convex portions derived from the graphitized particles. These convex portions have a specific relationship. | 06-10-2010 |
20100166454 | CHARGING MEMBER, PROCESS FOR ITS PRODUCTION, PROCESS CARTRIDGE - Concerned with a charging member in the conductive surface layer of which the conductive particles are so kept from agglomerating as to make charging performance not easily change even where the surface layer expands and contracts repeatedly in various environments. The charging member is a charging member having a conductive substrate and formed on the substrate a conductive elastic layer and a conductive surface layer. The elastic layer contains a polymer having a unit coming from ethylene oxide, and the surface layer contains a binder resin and graphitized particles. The binder resin contains a resin having in the molecule a urethane linkage or a siloxane linkage, or a urethane linkage and a siloxane linkage, and the graphitized particles have a graphite (002) plane lattice spacing of from 0.3362 nm or more to 0.3449 nm or less. | 07-01-2010 |
20120288302 | ELECTRO-CONDUCTIVE MEMBER FOR ELECTROPHOTOGRAPHY, ELECTROPHOTOGRAPHIC APPARATUS, AND PROCESS CARTRIDGE - When a polymer blend of an NBR and an alkylene oxide-polymerized polymer is used as the electro-conductive elastic layer of an electro-conductive member for electrophotography, a change in shape of the electro-conductive member occurs owing to its expansion due to water absorption, thereby causing image unevenness in some cases. In addition, when the ratio at which the alkylene oxide-polymerized polymer is blended is reduced for suppressing the shape change due to water absorption, image unevenness resulting from the insufficiency of electro-conductivity occurs in some cases. When an electro-conductive member for electrophotography having an electro-conductive elastic layer containing an NBR to which a specific alkylene oxide oligomer is graft-bonded is used, high ionic electro-conductivity is obtained and a change in its shape due to water absorption is reduced. | 11-15-2012 |
20130272747 | CHARGING MEMBER, PROCESS FOR ITS PRODUCTION, AND ELECTROPHOTOGRAPHIC APPARATUS - To provide a charging member that can not easily cause faulty cleaning on a photosensitive member while having a flexibility high enough to form a nip between it and the photosensitive member in a sufficient width. The charging member has an electro-conductive support and an elastic layer that is a surface layer, which elastic layer has at its surface a region having been cured by irradiation with electron rays, where this region supports spherical polyethylene particles in such a state that the spherical polyethylene particles are exposed to the surface of the elastic layer, thereby making the surface roughened. | 10-17-2013 |
20130302064 | CHARGING ROLLER AND PROCESS FOR ITS PRODUCTION - A roller for electrophotography is provided which has an electrically conductive support and an elastic layer as a surface layer, where the elastic layer holds spherical particles each having a plane on their peripheral surfaces, in such a way that part or the whole of the plane comes exposed to the surface of the elastic layer, and the plane of each of the spherical particles standing exposed to the surface of the elastic layer and a plane that is i) orthogonal to a straight line passing through an axis of a section orthogonal to an axis of the roller for electrophotography and being directed toward the peripheral surface of the roller for electrophotography and is ii) tangential to the peripheral surface of the roller for electrophotography forms an acute internal angle. | 11-14-2013 |
20130310239 | CHARGING MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS - The present invention provides a charging member having an elastic layer on a surface thereof in which occurrence of compression set is reduced. The charging member includes an electro-conductive support and an elastic layer provided on the support as a surface layer, wherein the elastic layer is a rubber layer made of a crosslinked product of a rubber mixture including acrylonitrile butadiene rubber and polybutadiene, the polybutadiene includes 1,2-syndiotactic polybutadiene, and the elastic layer is formed by irradiating a surface of the rubber layer with electron rays. | 11-21-2013 |
20140023960 | ELECTROPHOTOGRAPHIC MEMBER, METHOD FOR PRODUCING THE SAME, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS - An electrophotographic member including an electrically conductive substrate and an electrically conductive resin layer corresponding to a surface layer. The resin layer includes electrically conductive particles and a binder resin. The binder resin is a polymer in which a polymer chain having at least one unit selected from the group consisting of units represented by the following formulas (1) and (2) and at least one unit selected from the group consisting of units represented by the following formulas (3) and (4) is crosslinked by at least one organopolysiloxane chain selected from the group consisting of structures represented by the following formulas (5) and (6): | 01-23-2014 |
20140128233 | CHARGING MEMBER, MANUFACTURING METHOD THEREFOR, A PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC APPARATUS - To provide a charging member which suppresses the generation of density nonuniformity in an electrophotographic image caused by charge nonuniformity due to adhesion of charged substances, such as toner particles. There is provided a charging member which has a surface layer, the surface layer includes conductive zinc oxide whiskers each formed of a nuclear portion and four needle crystal portions extending radially outward therefrom, and the needle crystal portions are exposed to form convex portions of a surface of the surface layer. | 05-08-2014 |