Abstract: A method for manufacturing a low-cost electrophotographic elastic roller having a good dimensional precision is provided. In that method, in which both end parts of a shaft core body are gripped and fixed in a vertical direction, an inclination of a central axis is corrected, a circular coating head including a circular slit is used so that the shaft core body is moved in the direction, and a elastic layer material is ejected from the slit to be coated on the shaft core body, the method includes: a maximum deflection coordinate in a longitudinal direction of the shaft core body is detected with a central axis of the shaft core body as a base point coordinate before coating; a central position of the head is moved at constant from the base point to the maximum during coating, and the position is moved to the base point after the head has reached the maximum.

Abstract: An electrophotographic cleaning blade is provided which is free of blade turning-up coming from both end portions of the blade in its lengthwise direction. The cleaning blade having a blade formed of a polyurethane resin, which is to come into touch with the surface of a photosensitive drum of an electrophotographic apparatus to remove a toner remaining thereon, and a support member which holds the blade. The blade has a polyurethane resin portion having a dynamic hardness of 0.05 mN/?m2 or more and 0.16 mN/?m2 or less and a high-hardness portion having a dynamic hardness 1.3 times or more and 30 times or less the dynamic hardness of the polyurethane resin portion, provided at each end portion of the blade in its lengthwise direction at its part coming into touch with the photosensitive drum.

Abstract: A conductive rubber roller comprising a conductive core material and provided thereon a rubber layer; the rubber layer being formed by using a rubber composition containing as rubber components at least a polar rubber and an ethylene oxide-propylene oxide-allyl glycidyl ether terpolymer; the ethylene oxide-propylene oxide-allyl glycidyl ether terpolymer having a melt peak temperature of from 20 to 30° C. and a melt enthalpy change ?H of from 40 to 70 mJ/mg as measured with a differential scanning calorimeter; and the allyl glycidyl ether in the ethylene oxide-propylene oxide-allyl glycidyl ether terpolymer being in a copolymerization ratio of from more than 10 mol % to 20 mol % or less.

Abstract: A method for manufacturing a centrifugal casting die includes the steps of supplying a first liquid agent for forming a backup layer to be releasably bonded to an inner surface of a cylindrical die, rotating the die body so that the first liquid agent is uniformly spread over the entirety of the inner surface of the die body, and curing the first liquid agent spread over the entirety of the inner surface of the die body to form the backup layer. A second liquid agent is applied to be bonded to be integral with an inner surface of the backup layer to form a top layer. Then the die body is rotated so that the second liquid agent is uniformly spread over the entirety of the inner surface of the backup layer and cured to form the top layer. The top layer releasably holds a centrifugally casting material supplied to the inner surface thereof.

Abstract: There is provided a cleaning blade for an electrophotographic apparatus having good cleaning performance both immediately after long-time shutdown under low temperature environment and during continuous use under low temperature environment even when spherical toner having a small diameter is used. A cleaning blade for an electrophotographic apparatus having an elastic blade member which is brought into contact with an image bearing member and frictionally slid to remove remaining toner, wherein the elastic blade member satisfies (1) to (4): (1) the stress-relaxation rate represented by the formula (a) at 10° C.

Abstract: A blade for electrophotographic apparatus which has a blade member formed of a polyurethane resin, wherein the polyurethane resin is a resin produced by using a polyurethane raw-material composition containing at least the following components (A) to (E): (A) a polyisocyanate; (B) a polyol having a number average molecular weight of 2,000 or more and 4,000 or less; (C) a chain extender having a molecular weight of 200 or less: (D) a polyol having a number average molecular weight which is smaller than the number average molecular weight of the component-(B) polyol and is larger than the molecular weight of the component-(C) chain extender; and (E) a urethane curing catalyst.

Abstract: This invention provides a process for producing a conductive rubber roller having small aspect ratios of inner and outer diameters, having a stable measure of its inner diameter, having uniform cell distribution and being free from non-uniformity of hardness and electrical resistance in the peripheral direction. The process has a step of continuously extruding a tube composed of a specific unvulcanized rubber composition from a rubber extruder in a microwave vulcanizing unit, and a step of foaming and vulcanizing the tube by using a microwave irradiator having a microwave irradiation zone 4 m or less in length while being transported at given speed. The foamed rubber tube has an inner diameter 20 to 35% smaller than the outer diameter of the conductive core material over the whole region in the lengthwise direction, and the conductive core material is press-fitted into the foamed rubber tube without using any adhesive.

Abstract: A conductive rubber roller and transfer roller whose resistance value is easily controlled and which lowers contamination of a charged member and has excellent electric variability and compressive permanent set is provided at low cost. There is provided a conductive rubber roller for use in an electrophotographic process, wherein a rubber component of the conductive rubber roller has at least acrylonitrile butadiene rubber whose acrylonitrile content is 15% by mass to 25% by mass (both inclusive) and weight average molecular weight (Mw) is 500,000 to 1,000,000 (both inclusive), and epichlorohydrin type rubber whose ethylene oxide content is not less than 70% by mole to less than 90% by mole; and the acrylonitrile butadiene rubber is contained in an amount of 5 parts by mass to 80 parts by mass (both inclusive) in 100 parts by mass of the rubber component.

Abstract: An electroconductive rubber roller constituted of an electroconductive metal core and an electroconductive crosslinked rubber layer including an epichlorohydrin-based rubber, wherein the epichlorohydrin-based rubber is at least one copolymer selected from the group consisting of an epichlorohydrin-ethylene oxide copolymer and an epichlorohydrin-ethylene oxide-allyl glycidyl ether ternary copolymer. The ethylene oxide unit in the epichlorohydrin-based rubber is in a content of 40 to 90 mol %, and, the electroconductive crosslinked rubber layer has a heat quantity (enthalpy: ?H) 5 mJ/mg or less as measured by a differential scanning calorimetry (DSC) and indicated by a peak appearing within a range of ?20 to 150° C.

Abstract: A process produces a conductive rubber roller having small aspect ratios of inner and outer diameters, having a stable measure of its inner diameter, having uniform cell distribution and being free from non uniformity of hardness and electrical resistance in the peripheral direction. The process has a step of continuously extruding a tube composed of a specific unvulcanized rubber composition from a rubber extruder in a microwave vulcanizing unit, and a step of foaming and vulcanizing the tube by using a microwave irradiator having a microwave irradiation zone 4 m or less in length while being transported at given speed. The foamed rubber tube has an inner diameter 20 to 35% smaller than the outer diameter of the conductive core material over the whole region in the lengthwise direction, and the conductive core material is press fitted into the foamed rubber tube without using any adhesive.

Abstract: A copolymer obtained by copolymerizing at least one monomer selected from specific acrylate or methacrylate monomers, at least one monomer selected from specific amino group-containing monomers and at least one monomer selected from specific polar group-containing monomers. A resin for electrophotographic functional component parts, which contains this copolymer, a developing roller in which a cover layer serving as a surface layer contains the copolymer as a positive charge control resin, and an electrophotographic apparatus that includes the developing roller.

Abstract: An electrophotographic cleaning blade is provided which is free of blade turning-up coming from both end portions of the blade in its lengthwise direction. The cleaning blade having a blade formed of a polyurethane resin, which is to come into touch with the surface of a photosensitive drum of an electrophotographic apparatus to remove a toner remaining thereon, and a support member which holds the blade. The blade has a polyurethane resin portion having a dynamic hardness of 0.05 mN/?m2 or more and 0.16 mN/?m2 or less and a high-hardness portion having a dynamic hardness 1.3 times or more and 30 times or less the dynamic hardness of the polyurethane resin portion, provided at each end portion of the blade in its lengthwise direction at its part coming into touch with the photosensitive drum.

Abstract: A blade for an electrophotographic apparatus is provided which is prevented from turning up, achieves wear resistance, and has excellent cleaning properties. The blade is composed of a support member and a blade member formed of a thermosetting polyurethane elastomer, which are joined together. The blade member has a structure in which a nitrogen concentration continuously increases from the inside of a contact part coming into contact with a counterpart member toward the surface of the contact part.

Abstract: A mold for use in producing a molded body of an elastomer has a holding layer and a releasing layer on an inner periphery surface of a main body of a die. The releasing layer is formed of an addition two-component liquid silicone having a polysilazane-based or polysiloxane-based chain as a main chain, contains 0.5 mass % or less of a component which volatilizes at a curing temperature of a liquid elastomer raw material, does not contain silica, has International Rubber Hardness Degree of 50 to 85 degrees, and contains a solid lubricant having an average particle size of 2 to 20 ?m. The present invention also provides a method for manufacturing a blade for an electrophotographic apparatus by using the mold and a developer amount controlling blade having specific load length ratio and ten-point average roughness in which a blade member is manufactured with the method.

Abstract: A toner supplying roller is provided in which a polyurethane foam layer can be obtained without decreasing the reactivity of the polyurethane material, and in which contamination by a catalyst remaining in the polyurethane foam layer is suppressed, so that a good image can be obtained. Moreover, the toner supplying roller has suitable aperture cells in the surface, suitably performs the scraping off of the development residual toner and toner supply between the toner supplying roller and the developing roller, and forms a uniform toner thin film on the developing roller, so that a good image can be obtained. In a toner supplying roller including a polyurethane foam layer that is formed on the mandrel periphery using a polyurethane material including a polyol and a polyisocyanate, the polyol and the polyisocyanate have an amine number of 3 mg KOH/g or more and 15 mg KOH/g or less in total.

Abstract: A cleaning blade is provided which does not cause contamination of other parts even when being stored for a long period of time in a high temperature and high humidity environment. The cleaning blade is set in an image forming apparatus employing an electrostatic transfer process, including a blade member and a support member to rub and remove residual toner remaining on a photosensitive drum provided to the image forming apparatus, in which the total amount of nitrogen-containing compounds extracted with methanol from the cleaning blade is 12 ?g or less per cm of the cleaning blade in its longitudinal direction.

Abstract: To provide a positive charge control resin with which an electrophotographic functional component part coming into contact with a toner can be made chargeable in a polarity reverse to the polarity of the toner, and which has superior dispersibility in, and compatibility with, a main binder. The present invention is a positive charge control resin having a copolymer obtained by polymerizing specific acrylate or methacrylate monomer, amino-group-containing monomer(s) and carboxyl-group-containing monomer(s) as copolymerization components.

Abstract: A developer level control blade is provided which can form a developer layer on a developer carrying member in a proper thickness and in a uniform state and can keep the developer, in particular, color toner particles from melt-adhering to the charge control face so that faulty images such as lines and non-uniformity can be kept from occurring. Also provided is a process for manufacturing this developer level control blade. The process for manufacturing the developer level control blade is characterized by having the steps of extruding a blade member material melted to liquefy, covering therewith a support member thin-plate metal member at an edge portion thereof to join the both together, and cooling the blade member material to solidify, followed by cutting in a preset length.

Abstract: A centrifugal casting die according to the present invention includes a cylindrical die body, a backup layer releasably bonded to the inner surface 12b of the die body, and a top layer bonded to be integral to the inner surface of the backup layer, for holding a centrifugally casting material supplied to the inner surface thereof, whereby the centrifugally casting material having a uniform thickness is easily releasable from the centrifugal casting die without using a die-lubricant.

Abstract: A conductive rubber roller having a rubber layer on a conductive core material. The rubber composition constituting the rubber layer contains a rubber component and a filler. The rubber component contains an epichlorohydrin rubber. The filler includes carbon black (A) having a nitrogen adsorption specific surface area (N2SA) of 20 m2/g to 40 m2/g and having a dibutyl phthalate (DBP) oil absorption of 80 ml/100 g to 100 ml/100 g and carbon black (B) having a nitrogen adsorption specific surface area (N2SA) of 15 m2/g or less and having a dibutyl phthalate (DBP) oil absorption of 40 ml/100 g or less. The carbon black (A) is in a content of 10 parts by mass to 30 parts by mass and the carbon black (B) is in a content of 20 parts by mass to 60 parts by mass or less, based on 100 parts by mass of the rubber component.