Abstract: Provided is a means in which in a tandem type electrophotographic image forming apparatus, image deletion of a formed image is suppressed, passing through of a toner is suppressed, and the lifetime of an organic photoreceptor and the apparatus itself is prolonged. The invention relates to a tandem type electrophotographic image forming apparatus using an organic photoreceptor in which at least a charge generating layer and a charge transfer layer are sequentially laminated on a conductive support body, in which in at least one of combinations of two adjacent image forming units including toners having colors different from each other, a linear pressure P1 of a cleaning blade A included in the image forming unit disposed on an upstream side, and a linear pressure P2 of a cleaning unit blade B included in the image forming unit disposed on a downstream side, satisfy a predetermined relationship.

Abstract: A tandem type electrophotographic image forming device using an organic photoreceptor, includes a plurality of image forming units each including at least: an electrostatic latent image former; a developer; a lubricant supplier; and a cleaner, wherein at least one combination composed of the two adjacent image forming units including toners having different colors satisfies the following formula (1) if a universal hardness of an organic photoreceptor A included in the image forming unit disposed on an upstream side is represented by Ha, and a universal hardness of an organic photoreceptor B included in the image forming unit disposed on a downstream side is represented by Hb.

Abstract: A electrophotographic image forming device using an organic photoreceptor, includes a plurality of image forming units each including at least: an electrostatic latent image former; a developer; a lubricant supplier; and a cleaner including a cleaning blade and a cleaning assist brush, wherein at least one combination composed of two adjacent image forming units including toners having different colors satisfies the following formula (1) if a ratio of a circumferential speed of the cleaning assist brush with respect to a circumferential speed of an organic photoreceptor included in an image forming unit A is represented by ?1 and a ratio of a circumferential speed of the cleaning assist brush with respect to a circumferential speed of an organic photoreceptor included in an image forming unit B is represented by ?2.

Abstract: A electrophotographic image forming device using an organic photoreceptor, includes a plurality of image forming units each including at least: an electrostatic latent image former; a developer; a lubricant supplier; and a cleaner including a cleaning blade and a cleaning assist brush, wherein at least one combination composed of two adjacent image forming units including toners having different colors satisfies the following formula (1) if a ratio of a circumferential speed of the cleaning assist brush with respect to a circumferential speed of an organic photoreceptor included in an image forming unit A is represented by ?1 and a ratio of a circumferential speed of the cleaning assist brush with respect to a circumferential speed of an organic photoreceptor included in an image forming unit B is represented by ?2.

Abstract: Provided is a means in which in a tandem type electrophotographic image forming apparatus, image deletion of a formed image is suppressed, passing through of a toner is suppressed, and the lifetime of an organic photoreceptor and the apparatus itself is prolonged. The invention relates to a tandem type electrophotographic image forming apparatus using an organic photoreceptor in which at least a charge generating layer and a charge transfer layer are sequentially laminated on a conductive support body, in which in at least one of combinations of two adjacent image forming units including toners having colors different from each other, a linear pressure P1 of a cleaning blade A included in the image forming unit disposed on an upstream side, and a linear pressure P2 of a cleaning unit blade B included in the image forming unit disposed on a downstream side, satisfy a predetermined relationship.

Abstract: A tandem type electrophotographic image forming device using an organic photoreceptor, includes a plurality of image forming units each including at least: an electrostatic latent image former; a developer; a lubricant supplier; and a cleaner, wherein at least one combination composed of the two adjacent image forming units including toners having different colors satisfies the following formula (1) if a universal hardness of an organic photoreceptor A included in the image forming unit disposed on an upstream side is represented by Ha, and a universal hardness of an organic photoreceptor B included in the image forming unit disposed on a downstream side is represented by Hb.

Abstract: Provided is an electrophotographic photoreceptor including a conductive support having thereon an intermediate layer, a charge generating layer, a charge transporting layer, and a protective layer sequentially laminated in that order, wherein the intermediate layer contains rutile type titanium oxide particles, and 50% or more of the rutile type titanium oxide particles have an organic compound on a surface of the titanium oxide particles; the charge generating layer has a pigment containing a 2,3-butanediol adduct of a phthalocyanine compound; the charge transporting layer contains a charge transporting material having an ionization potential of 5.45 to 5.60 eV; and the protective layer contains metal oxide particles and the charge transporting material in a cured resin prepared by curing a polymerizable compound.

Abstract: An electrophotographic image forming apparatus using an organic photoreceptor in which at least a charge generation layer, a charge transport layer, and a protective layer are laminated in order on a conductive support includes at least a unit for supplying a lubricant onto a surface of the organic photoreceptor and a unit for removing toner remaining on the surface of the organic photoreceptor with a cleaning blade, and satisfying the following conditions (1) to (3): (1) the protective layer of the organic photoreceptor contains at least metal oxide fine particles in a cured resin obtained by curing a polymerizable compound; (2) a universal hardness of the surface of the organic photoreceptor is in a range of 220 to 280 N/mm2; and (3) a JIS-A hardness of a portion of the cleaning blade to be abutted on the organic photoreceptor is in a range of 70 to 78°.

Abstract: An electrophotographic image forming apparatus using an organic photoreceptor in which at least a charge generation layer, a charge transport layer, and a protective layer are laminated in order on a conductive support includes at least a unit for supplying a lubricant onto a surface of the organic photoreceptor and a unit for removing toner remaining on the surface of the organic photoreceptor with a cleaning blade, and satisfying the following conditions (1) to (3): (1) the protective layer of the organic photoreceptor contains at least metal oxide fine particles in a cured resin obtained by curing a polymerizable compound; (2) a universal hardness of the surface of the organic photoreceptor is in a range of 220 to 280 N/mm2; and (3) a JIS-A hardness of a portion of the cleaning blade to be abutted on the organic photoreceptor is in a range of 70 to 78°.

Abstract: An imaging apparatus including: an electrophotographic photoreceptor; a charging unit to charge the surface of the electrophotographic photoreceptor; an exposing unit to perform exposure of the electrophotographic photoreceptor charged by the charging unit; a developing unit to feed a toner to the electrophotographic photoreceptor exposed by the exposing unit to form a toner image; a transfer unit to transfer the toner image formed on the electrophotographic photoreceptor; a lubricant feeding unit to feed a lubricant onto the surface of the electrophotographic photoreceptor; and a cleaning unit to remove the residual toner on the surface of the electrophotographic photoreceptor, wherein the electrophotographic photoreceptor includes a conductive support, a photoreceptive layer, and a protective layer disposed in sequence, the protective layer includes a resin containing a particulate P-type semiconductor, and the protective layer has a surface roughness Rz of 0.030 ?m or more and 0.075 ?m or less.

Abstract: An electrophotographic photoreceptor includes: a conductive holder; and at least a charge producing layer and a charge transport layer disposed on the conductive holder in order. The charge transport layer contains at least a binder resin, a charge transport agent and a p-type metal oxide particle.

Abstract: Provided is an electrophotographic photoreceptor including a conductive support having thereon an intermediate layer, a charge generating layer, a charge transporting layer, and a protective layer sequentially laminated in that order, wherein the intermediate layer contains rutile type titanium oxide particles, and 50% or more of the rutile type titanium oxide particles have an organic compound on a surface of the titanium oxide particles; the charge generating layer has a pigment containing a 2,3-butanediol adduct of a phthalocyanine compound; the charge transporting layer contains a charge transporting material having an ionization potential of 5.45 to 5.60 eV; and the protective layer contains metal oxide particles and the charge transporting material in a cured resin prepared by curing a polymerizable compound.

Abstract: An electrophotographic image forming apparatus using an organic photoreceptor in which at least a charge generation layer, a charge transport layer, and a protective layer are laminated in order on a conductive support includes at least a unit for supplying a lubricant onto a surface of the organic photoreceptor and a unit for removing toner remaining on the surface of the organic photoreceptor with a cleaning blade, and satisfying the following conditions (1) to (3): (1) the protective layer of the organic photoreceptor contains at least metal oxide fine particles in a cured resin obtained by curing a polymerizable compound; (2) a universal hardness of the surface of the organic photoreceptor is in a range of 220 to 280 N/mm2; and (3) a JIS-A hardness of a portion of the cleaning blade to be abutted on the organic photoreceptor is in a range of 70 to 78°.

Abstract: An imaging apparatus including: an electrophotographic photoreceptor; a charging unit to charge the surface of the electrophotographic photoreceptor; an exposing unit to perform exposure of the electrophotographic photoreceptor charged by the charging unit; a developing unit to feed a toner to the electrophotographic photoreceptor exposed by the exposing unit to form a toner image; a transfer unit to transfer the toner image formed on the electrophotographic photoreceptor; a lubricant feeding unit to feed a lubricant onto the surface of the electrophotographic photoreceptor; and a cleaning unit to remove the residual toner on the surface of the electrophotographic photoreceptor, wherein the electrophotographic photoreceptor includes a conductive support, a photoreceptive layer, and a protective layer disposed in sequence, the protective layer includes a resin containing a particulate P-type semiconductor, and the protective layer has a surface roughness Rz of 0.030 ?m or more and 0.075 ?m or less.

Abstract: In an organic photoreceptor that has a protective layer formed on an organic photosensitive layer, the protective layer contains; a cured resin constituent obtained by polymerizing a polymerizable compound in the presence of a radical scavenger represented by the general formula (2); metal oxide microparticles; and a compound represented by the general formula (1) as a charge transport substance, and the relational expression (1): 80/A?B?160/A and the relational expression (2): 12?A?25 are satisfied when the volume ratio (volume %) of the metal oxide microparticles in the protective layer and the volume ratio (volume %) of the compound represented by the general formula (1) in the protective layer are respectively denoted by A and B.

Abstract: An electrophotographic photoreceptor includes: a conductive support; a photosensitive layer including at least an organic material; and a surface protective layer, wherein the photosensitive layer and the surface protective layer are provided on the conductive support, and the surface protective layer includes a photo-curable crosslinking monomer and a charge transport material including a mixture of a plurality of stereoisomers.

Abstract: An electrophotographic photoreceptor includes: a conductive holder; and at least a charge producing layer and a charge transport layer disposed on the conductive holder in order. The charge transport layer contains at least a binder resin, a charge transport agent and a p-type metal oxide particle.

Abstract: In an organic photoreceptor that has a protective layer formed on an organic photosensitive layer, the protective layer contains; a cured resin constituent obtained by polymerizing a polymerizable compound in the presence of a radical scavenger represented by the general formula (2); metal oxide microparticles; and a compound represented by the general formula (1) as a charge transport substance, and the relational expression (1): 80/A?B?160/A and the relational expression (2): 12?A?25 are satisfied when the volume ratio (volume %) of the metal oxide microparticles in the protective layer and the volume ratio (volume %) of the compound represented by the general formula (1) in the protective layer are respectively denoted by A and B.

Abstract: The invention provides a means for improving the abrasion resistance and the scratch resistance of a protection layer by increasing the surface hardness of the protection layer of an organic photoreceptor. The invention is an organic photoreceptor constituted by laminating on an electroconductive substrate, a photosensitive layer and a protection layer successively, wherein the protection layer comprises a charge transport substance represented by the following general formula (1), a resin component obtained by curing a curable compound and tin oxide treated with a surface preparation agent having a reactive organic group, and a silica particle: in the general formula (1), R1 and R2 are each independently hydrogen atoms or methyl groups, and R3 is a straight-chain or branched alkyl group having 1 to 5 carbon atoms.

Abstract: The invention provides a means for improving the abrasion resistance and the scratch resistance of a protection layer by increasing the surface hardness of the protection layer of an organic photoreceptor. The invention is an organic photoreceptor constituted by laminating on an electroconductive substrate, a photosensitive layer and a protection layer successively, wherein the protection layer comprises a charge transport substance represented by the following general formula (1), a resin component obtained by curing a curable compound and tin oxide treated with a surface preparation agent having a reactive organic group, and a silica particle; in the general formula (1), R1 and R2 are each independently hydrogen atoms or methyl groups, and R3 is a straight-chain or branched alkyl group having 1 to 5 carbon atoms.