Abstract: A development device includes a developer container, a developer carrier, exposed partly from a casing, facing a latent image carrier in a development area, a magnetic field generator inside the developer carrier, having multiple magnetic poles including a conveyance pole to convey the developer downstream from the development area to a developer release portion, a developer agitator, and a developer regulator. A predetermined gap is kept between an outer surface of the developer carrier and an inner wall of the casing downstream from an opening of the casing, upstream from a developer release portion, in a direction in which the developer carrier rotates. Multiple recesses are formed in the outer surface of the developer carrier at a pitch in a circumferential direction shorter than half a width of a magnetic flux density of the developer conveyance pole in a direction perpendicular to an axial direction of the developer carrier.

Abstract: A develop roller includes a magnet roller, and a develop sleeve containing the magnet roller and comprising a plurality of depressions in an elliptic shape regularly arranged with an interval in a longitudinal direction on a surface onto which developer is attracted by a magnetic force of the magnet roller, wherein the depressions are arranged such that a longitudinal direction of the depressions is intersected with the longitudinal direction of the develop sleeve, and a downstream side of the depressions are formed to be deeper than an upstream side in a rotary direction of the develop sleeve.

Abstract: A development device including a developer container, a developer bearer, a magnetic field generator, a developer agitator to supply the developer to the developer bearer, and a developer regulator to adjust a layer thickness of the developer carried on the developer bearer. Multiple oval recesses oblique to the axial direction of the developer bearer are formed in the outer circumferential surface of the developer bearer and arranged in a circumferential direction and the axial direction thereof. An upstream inner wall of the recess in the rotational direction of the developer bearer applies a force to the developer as the developer bearer rotates, and an angle between a long axis of the recess and the axial direction is set so that the force applied by the upstream inner wall of the recess has a component in a direction substantially identical to the developer conveyance direction of the developer agitator.

Abstract: A development roller includes a magnet roller and a rotatably supported development sleeve including inside thereof the magnet roller, the development sleeve is formed in a cylindrical shape and configured such that a shaft center of the cylindrical shape is inconsistent with a rotation axis of the development sleeve, the development sleeve includes an outer surface provided with many circular or elliptical depressions in a planar view, the depressions being regularly arranged at intervals, and a depth of the depression provided in a portion of the outer surface close to the rotation axis is larger than a depth of the depression provided in a portion of the outer surface far from the rotation axis.

Abstract: A development roller includes a magnet roller and a rotatably supported development sleeve including inside thereof the magnet roller, the development sleeve is formed in a cylindrical shape and configured such that a shaft center of the cylindrical shape is inconsistent with a rotation axis of the development sleeve, the development sleeve includes an outer surface provided with many circular or elliptical depressions in a planar view, the depressions being regularly arranged at intervals, and a depth of the depression provided in a portion of the outer surface close to the rotation axis is larger than a depth of the depression provided in a portion of the outer surface far from the rotation axis.

Abstract: An image forming device comprises a process cartridge. The process cartridge comprises a development roller. The development roller comprises a magnet roller and a developing sleeve 132. The magnet roller is fixed. The depressions 139 each having an oval shape are formed on the external surface of the developing sleeve 132. Both ends of the depressions 139 which are adjacent with each other along the longitudinal direction of the developing sleeve 132 are overlapped with each other and both ends of the depressions 139 which are adjacent with each other along the circumferential direction of the developing sleeve 132 are spaced with each other.

Abstract: A conductive member includes a conductive support and an electrical resistance adjusting layer formed on the conductive support. The electrical resistance adjusting layer includes a thermoplastic resin, a polymeric ion conductive material, and a graft copolymer which is compatible with both of the thermoplastic resin and the polymeric ion conductive material. The electrical resistance adjusting layer is formed in a sea-island structure formed from a sea portion made of the polymeric ion conductive material and island portions made of the thermoplastic resin, the island portions being dispersed in the sea portion and each of the island portions is formed in an elongate shape. A layer made of the graft copolymer is formed at boundaries between the thermoplastic resin and the polymeric ion conductive material.

Abstract: A development device including a developer container, a developer bearer, a magnetic field generator, a developer agitator to supply the developer to the developer bearer, and a developer regulator to adjust a layer thickness of the developer carried on the developer bearer. Multiple oval recesses oblique to the axial direction of the developer bearer are formed in the outer circumferential surface of the developer bearer and arranged in a circumferential direction and the axial direction thereof. An upstream inner wall of the recess in the rotational direction of the developer bearer applies a force to the developer as the developer bearer rotates, and an angle between a long axis of the recess and the axial direction is set so that the force applied by the upstream inner wall of the recess has a component in a direction substantially identical to the developer conveyance direction of the developer agitator.

Abstract: An electroconductive member including an electroconductive support, an electric resistance adjusting layer formed on the electroconductive support, and a top surface layer that coats the surface of the electric resistance adjusting layer, the top surface layer containing at least one oxygen-containing inorganic compound selected from among a composite oxide of silicon and aluminum, an oxygen-containing silicon compound, and an oxygen-containing aluminum compound.

Abstract: A develop roller includes a magnet roller, and a develop sleeve containing the magnet roller and comprising a plurality of depressions in an elliptic shape regularly arranged with an interval in a longitudinal direction on a surface onto which developer is attracted by a magnetic force of the magnet roller, wherein the depressions are arranged such that a longitudinal direction of the depressions is intersected with the longitudinal direction of the develop sleeve, and a downstream side of the depressions are formed to be deeper than an upstream side in a rotary direction of the develop sleeve.

Abstract: A development device includes a developer container, a developer carrier, exposed partly from a casing, facing a latent image carrier in a development area, a magnetic field generator inside the developer carrier, having multiple magnetic poles including a conveyance pole to convey the developer downstream from the development area to a developer release portion, a developer agitator, and a developer regulator. A predetermined gap is kept between an outer surface of the developer carrier and an inner wall of the casing downstream from an opening of the casing, upstream from a developer release portion, in a direction in which the developer carrier rotates. Multiple recesses are formed in the outer surface of the developer carrier at a pitch in a circumferential direction shorter than half a width of a magnetic flux density of the developer conveyance pole in a direction perpendicular to an axial direction of the developer carrier.

Abstract: A developing roller includes a developing sleeve and a magnet roller disposed within the developing sleeve to attract developer to an outer surface of the developing sleeve by magnetic force. The outer surface of the developing sleeve has a plurality of recesses of circular or elliptic shape in plan view regularly or irregularly arranged therein so as not to overlap.

Abstract: The present invention provides Cr-containing steel superior in heat fatigue characteristics, that is, Cr-containing steel superior in heat fatigue characteristics, characterized by containing, by mass %, C: 0.01% or less, N: 0.015% or less, Si: 0.8 to 1.0%, Mn: 0.2 to 1.5%, P: 0.03% or less, S: 0.01% or less, Ni: 0.2% or less, Cu: 0.2% or less, Cr: 13 to 15%, Mo: 0.1% or less, Nb: 0.3 to 0.5%, Ti: 0.05 to 0.2%, V: 0.01 to 0.2%, Al: 0.015 to 1.0%, and B: 0.0002 to 0.0010%, satisfying (Nb+1.9×Ti)/(C+N)?50, and having a balance of Fe and unavoidable impurities, wherein a 0.2% yield strength at 800° C. after aging at 800° C. for 100 hours or more is 20 MPa or more and a drawability value at 200° C. is 35% or more and wherein a soluble Nb amount+soluble Ti amount after aging at 800° C. for 100 hours or more is 0.08% or more.

Abstract: An image forming device comprises a process cartridge. The process cartridge comprises a development roller. The development roller comprises a magnet roller and a developing sleeve 132. The magnet roller is fixed. The depressions 139 each having an oval shape are formed on the external surface of the developing sleeve 132. Both ends of the depressions 139 which are adjacent with each other along the longitudinal direction of the developing sleeve 132 are overlapped with each other and both ends of the depressions 139 which are adjacent with each other along the circumferential direction of the developing sleeve 132 are spaced with each other.

Abstract: The present invention provides a conductive member 10 with a superior durability by controlling an electric resistance value of an electric resistance adjusting layer 2 within a semi conductive range, preventing an ion conductive material from bleeding out of the electric resistance adjusting layer 2 to avoid improper charging and avoiding strength decreasing of a weld portion of the electric resistance adjusting layer and an electric resistance value fluctuation. The electric resistance adjusting layer 2 is made from a resin composition prepared by melting and kneading a thermoplastic resin, a high molecular ion conductive material containing an alkali metal salt and a graft copolymer which has an affinity for both the thermoplastic resin and the high molecular ion conductive material.

Abstract: A conductive member to be disposed so as to abut on an image carrier is provided. The conductive member includes an elongate conductive supporter, an electrical resistance adjusting layer formed on a circumferential surface of the supporter, and a pair of gap maintaining members provided respectively to the two ends of the adjusting layer. A gap with a certain clearance between an outer circumferential surface of the adjusting layer and an outer circumferential surface of the image carrier provided in parallel to the adjusting layer is formed. A stepped portion is formed in a joint section between the adjusting layer and each of the gap maintaining members with the joint section. An inclination is formed so as to be continuously inclined from the outer circumferential surface of each of the gap maintaining members to the outer circumferential surface of the adjusting layer in the stepped portion.

Abstract: A conductive member includes a conductive support and an electrical resistance adjusting layer formed on the conductive support. The electrical resistance adjusting layer includes a thermoplastic resin, a polymeric ion conductive material, and a graft copolymer which is compatible with both of the thermoplastic resin and the polymeric ion conductive material. The electrical resistance adjusting layer is formed in a sea-island structure formed from a sea portion made of the polymeric ion conductive material and island portions made of the thermoplastic resin, the island portions being dispersed in the sea portion and each of the island portions is formed in an elongate shape. A layer made of the graft copolymer is formed at boundaries between the thermoplastic resin and the polymeric ion conductive material.

Abstract: An conductive member includes a long conductive supporting body to which a predetermined potential is applied, extending from one side to the other side, an electric resistance adjusting layer, which is formed to surround a circumference surface of the conductive supporting body and adjusts an electric resistance, and a surface protection layer, which is provided to cover a surface of the electric resistance adjusting layer and protects the surface of the electric resistance adjusting layer, and the electric resistance adjusting layer contains a thermoplastic resin material having an ether group in a molecular and an organic phosphonium salt.

Abstract: A developing roller includes a developing sleeve and a magnet roller disposed within the developing sleeve to attract developer to an outer surface of the developing sleeve by magnetic force. The outer surface of the developing sleeve has a plurality of recesses of circular or elliptic shape in plan view regularly or irregularly arranged therein so as not to overlap.

Abstract: An electrical conductive member is configured to prevent a shape distortion in gap retaining members caused by that the gap retaining members are fitted to an end surface of an electric resistance adjusting layer, and to be able to maintain a gap between the electric residence adjusting layer and an image carrier for a long-term in a constant state with a high accuracy.