Abstract: An electrophotographic roller comprising a substrate and a foam layer on an outer peripheral surface of the substrate, the foam layer constituting an outer surface of the electrophotographic roller, the foam layer comprising cells each of which opens on the outer surface, and the foam layer having a zero-point charge measured using a standard carrier of 40 ?C/g or more.

Abstract: An electrophotographic roller comprising a substrate and a foam layer on an outer peripheral surface of the substrate, the foam layer constituting an outer surface of the electrophotographic roller, the foam layer comprising cells each of which opens on the outer surface, and the foam layer having a zero-point charge measured using a standard carrier of 40 ?C/g or more.

Abstract: Provided is such a conductive member that a change in its electrical resistance value caused by its long-term use is reduced to the extent possible. The conductive member has a conductive support and a conductive layer, the conductive layer contains a rubber composition formed of a modified epichlorohydrin rubber, and the modified epichlorohydrin rubber has a unit represented by the following formula (1). In the formula (1), R1, R2, and R3 each independently represent hydrogen or a saturated hydrocarbon group having 1 to 18 carbon atoms.

Abstract: An electrophotographic member has an electro-conductive substrate, an elastic layer on the substrate and a coating layer on the elastic layer. The elastic layer has an elastic modulus of 0.5 MPa to 3.0 MPa and the coating layer has an elastic modulus of 5.0 MPa to 100.0 MPa as measured in an environment of a temperature of 30° C. and a relative humidity of 80%.

Abstract: Provided is a developing roller comprising an electroconductive substrate and an electroconductive layer thereon, the electroconductive layer retaining resin particles so that at least a part of each of the resin particles is exposed on an outer surface of the developing roller; the outer surface of the developing roller constituted by electrically insulating domains and an electroconductive matrix, assuming that a square region 200-?m in a side is put on the outer surface of the developing roller, the square region including the domains, among the domains in the square region at least two of them satisfying specific condition, and assuming that the outer surface of the developing roller is charged, and creating a potential map of the charged outer surface of the developing member, the two domains satisfying the specific condition being ascertained in the potential map.

Abstract: Provided is a developing roller comprising an electroconductive substrate and an electroconductive layer thereon, the electroconductive layer retaining resin particles so that at least a part of each of the resin particles is exposed on an outer surface of the developing roller; the outer surface of the developing roller constituted by electrically insulating domains and an electroconductive matrix, assuming that a square region 200-?m in a side is put on the outer surface of the developing roller, the square region including the domains, among the domains in the square region at least two of them satisfying specific condition, and assuming that the outer surface of the developing roller is charged, and creating a potential map of the charged outer surface of the developing member, the two domains satisfying the specific condition being ascertained in the potential map.

Abstract: To provide an electrophotographic member causing less change in toner conveyance even used in a high-temperature and high-humidity environment. The electrophotographic member has an electro-conductive substrate, an elastic layer on the substrate and a coating layer on the elastic layer. The elastic layer has a first protrusion on a surface thereof on a side opposite to a side facing the substrate. The electrophotographic member has, on an outer surface thereof, a second protrusion derived from the first protrusion. The outer surface of the electrophotographic member has one or more of electrical insulating first region(s) and an electro-conductive second region. The elastic layer has an elastic modulus of 0.5 MPa or more to 3.0 MPa or less and the coating layer has an elastic modulus of 5.0 MPa or more to 100.0 MPa or less as measured in an environment of a temperature of 30° C. and a relative humidity of 80%.

Abstract: Provided is such a conductive member that a change in its electrical resistance value caused by its long-term use is reduced to the extent possible. The conductive member has a conductive support and a conductive layer, the conductive layer contains a rubber composition formed of a modified epichlorohydrin rubber, and the modified epichlorohydrin rubber has a unit represented by the following formula (1). In the formula (1), R1, R2, and R3 each independently represent hydrogen or a saturated hydrocarbon group having 1 to 18 carbon atoms.

Abstract: Provided is such a conductive member that a change in its electrical resistance value caused by its long-term use is reduced to the extent possible. The conductive member has a conductive support and a conductive layer, the conductive layer contains a rubber composition formed of a modified epichlorohydrin rubber, and the modified epichlorohydrin rubber has a unit represented by the following formula (1). In the formula (1), R1, R2, and R3 each independently represent hydrogen or a saturated hydrocarbon group having 1 to 18 carbon atoms.

Abstract: Provided are a developer carrying member, and a process cartridge and an electrophotographic apparatus using the developer carrying member, the developer carrying member including a substrate, an elastic layer, and a surface layer covering a surface of the elastic layer in which the surface layer contains a modified acrylic resin, and the modified acrylic resin has a constituent unit represented by the following structural formula (1). (R1 represents an alkyl group having 1 to 3 carbon atoms; U represents a urethane resin having, between two adjacent urethane bonds, a structure represented by the following structural formula (2), and at least one of structure selected from a structure represented by the following structural formula (3) and a structure represented by the following structural formula (4); and L represents a divalent linking group containing an ester bond (—O—C(?O)—)).

Abstract: Provided is such a conductive member that a change in its electrical resistance value caused by its long-term use is reduced to the extent possible. The conductive member has a conductive support and a conductive layer, the conductive layer contains a rubber composition formed of a modified epichlorohydrin rubber, and the modified epichlorohydrin rubber has a unit represented by the following formula (1). In the formula (1), R1, R2, and R3 each independently represent hydrogen or a saturated hydrocarbon group having 1 to 18 carbon atoms.

Abstract: Provided are a developer carrying member, and a process cartridge and an electrophotographic apparatus using the developer carrying member, the developer carrying member including a substrate, an elastic layer, and a surface layer covering a surface of the elastic layer in which the surface layer contains a modified acrylic resin, and the modified acrylic resin has a constituent unit represented by the following structural formula (1). (R1 represents an alkyl group having 1 to 3 carbon atoms; U represents a urethane resin having, between two adjacent urethane bonds, a structure represented by the following structural formula (2), and at least one of structure selected from a structure represented by the following structural formula (3) and a structure represented by the following structural formula (4); and L represents a divalent linking group containing an ester bond (—O—C(?O)—)).

Abstract: Provided is an electroconductive member that can demonstrate stable performance for a long period of time with an electric resistance value being hardly changed even by electrical conduction for a long period of time. An electroconductive member has a conductive mandrel, and a conductive layer provided on the outer periphery of the conductive mandrel. The conductive layer includes an organic polymeric compound as a binder, and a conductive particle dispersed in the organic polymeric compound, and the particle includes an organic-inorganic hybrid polymer having a specific structure.

Abstract: An electroconductive member excellent in durability even when applying direct current voltage over a long period of time is provided. Disclosed is an electroconductive member including an electroconductive mandrel and an electroconductive layer, wherein: the electroconductive layer includes a binder resin and an electroconductive metal oxide particle dispersed in the electroconductive layer; the metal oxide particle has a group represented by the following structural formula (1) on the surface of the metal oxide particle; and the group represented by the following structural formula (1) is introduced by substituting a hydrogen atom of a hydroxyl group as a functional group originating from the metal oxide particle, with the group represented by the following structural formula (1): —R—SO3H.

Abstract: Provided is a conductive member for electrophotography whose electrical resistance hardly increases even by long-term application of a high voltage. The conductive member for electrophotography is a conductive member for electrophotography, including: a conductive support; and a conductive elastic layer, in which: the elastic layer contains an A-B-A type block copolymer constituted of a non-ion conducting block (A block) and an ion conducting block (B block) having an ion exchange group; the block copolymer forms a microphase-separated structure; and the A block forms any structure selected from the group consisting of a spherical structure, a cylindrical structure, and a bicontinuous structure, and the B block forms a matrix for the structure.

Abstract: Provided is the following electro-conductive member for electrophotography. The electrical resistance of the member hardly increases even by long-term energization, and hence the member is conducive to stable formation of high-quality electrophotographic images. The electro-conductive member for electrophotography, comprises: an electro-conductive mandrel and an electro-conductive layer, wherein said electro-conductive layer contains an A-B-A type triblock copolymer in which an A-block is a polystyrene having a cation exchange group, and a B-block is a polyolefin, and wherein said A-B-A type triblock copolymer forms a microphase-separated structure comprising a matrix phase formed of said B-block, and one phase formed of the A-block and having a structure selected from the group consisting of a cylindrical structure, a bicontinuous structure and a lamellar structure.

Abstract: Provided is such a conductive member that a change in its electrical resistance value caused by its long-term use is reduced to the extent possible. The conductive member has a conductive support and a conductive layer, the conductive layer contains a rubber composition formed of a modified epichlorohydrin rubber, and the modified epichlorohydrin rubber has a unit represented by the following formula (1). In the formula (1), R1, R2, and R3 each independently represent hydrogen or a saturated hydrocarbon group having 1 to 18 carbon atoms.

Abstract: An electroconductive member excellent in durability even when applying direct current voltage over a long period of time is provided.

Abstract: Provided is the following electro-conductive member for electrophotography. The electrical resistance of the member hardly increases even by long-term energization, and hence the member is conducive to stable formation of high-quality electrophotographic images. The electro-conductive member for electrophotography, comprises: an electro-conductive mandrel and an electro-conductive layer, wherein said electro-conductive layer contains an A-B-A type triblock copolymer in which an A-block is a polystyrene having a cation exchange group, and a B-block is a polyolefin, and wherein said A-B-A type triblock copolymer forms a microphase-separated structure comprising a matrix phase formed of said B-block, and one phase formed of the A-block and having a structure selected from the group consisting of a cylindrical structure, a bicontinuous structure and a lamellar structure.

Abstract: Provided is an electroconductive member that can demonstrate stable performance for a long period of time with an electric resistance value being hardly changed even by electrical conduction for a long period of time. An electroconductive member has a conductive mandrel, and a conductive layer provided on the outer periphery of the conductive mandrel. The conductive layer includes an organic polymeric compound as a binder, and a conductive particle dispersed in the organic polymeric compound, and the particle includes an organic-inorganic hybrid polymer having a specific structure.