G03G21/1803

Image forming apparatus including drum cartridge attachable to drawer and pressing member for pressing drum cartridge attached to drawer downward
20210325823 · 2021-10-21 · ·

An image forming apparatus includes: a housing; a drawer movable between an inner position accommodated within the housing and an outer position exposed to an outside of the housing; a drum cartridge including a photosensitive drum and a drum frame; a developing cartridge; and a pressing member for pressing the drum frame. The drum frame includes: first and second side frames supporting first and second end portions of the photosensitive drum, respectively; and an upper frame connecting upper end portions of the first and second side frames to each other. In a state where the drum cartridge to which the developing cartridge has been attached is attached to the drawer and the drawer is in the inner position, the developing cartridge is positioned between the photosensitive drum and the upper frame, and the pressing member is positioned above the upper frame to press the upper frame downward.

Process cartridge with a coupling member having a movable force receiving portion

A process cartridge including a photosensitive drum; a developing roller; a rotatable roller having a rotation shaft in a position deviated from an axis of the developing roller; an Oldham coupling member at an end portion of the shaft of the rotatable roller; an urging member for urging the drive receiving portion; a supporting portion supporting the drive receiving portion; an abutting portion receiving the supporting portion urged by the urging member, an elastic sheet positioned to contact at least part of the Oldham coupling member, wherein the abutting portion is positioned outside an outer periphery of the drum on a plane perpendicular to the shaft of the rotatable roller.

Electrostatic charge image developer, process cartridge, image forming apparatus, and image forming method

An electrostatic charge image developer contains toner particles, layered-compound particles that are particles of a nitrogen-containing layered compound, and a resin-coated carrier that has magnetic particles and a resin layer covering the magnetic particles. The maximum height Ry of the roughness profile as defined in JIS B0601: 1994 of the surface of the resin-coated carrier is 0.01 μm or more and 0.20 μm or less.

Dispersant-attached polytetrafluoroethylene particle, composition, layer-shaped article, electrophotographic photoreceptor, process cartridge, and image forming apparatus
11067911 · 2021-07-20 · ·

A dispersant-attached polytetrafluoroethylene particle includes a polytetrafluoroethylene particle; and a dispersant that contains a fluorine atom and is attached to a surface of the polytetrafluoroethylene particle. The dispersant-attached polytetrafluoroethylene particle has a particle size distribution index [D.sub.50-D.sub.10] of 50 nm or more.

Electrophotographic photoreceptor, process cartridge, and image forming apparatus

An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer disposed on the conductive substrate. An outermost surface layer of the electrophotographic photoreceptor contains a fluorine-containing resin particle and a fluorine-based graft polymer having a fluorinated alkyl group. A ratio of an amount of a fluorine-based graft polymer separated from the fluorine-containing resin particle to a total amount of the fluorine-based graft polymer in the outermost surface layer is 15% or less.

Electrostatic image developing toner, electrostatic image developer, toner cartridge, process cartridge, image forming apparatus, and image forming method

An electrostatic image developing toner includes toner particles, layered compound particles, and inorganic particles. The proportion of irregular-shaped inorganic particles having a circularity of 0.5 or more and 0.9 or less and a size of 0.015 μm or more and 0.350 μm or less to the entire inorganic particles is 2% by number or more and 70% by number or less.

ELECTROSTATIC CHARGE IMAGE DEVELOPER, PROCESS CARTRIDGE, IMAGE FORMING APPARATUS, AND IMAGE FORMING METHOD

An electrostatic charge image developer contains toner particles, layered-compound particles that are particles of a nitrogen-containing layered compound, and a resin-coated carrier that has magnetic particles and a resin layer covering the magnetic particles. The maximum height Ry of the roughness profile as defined in JIS B0601: 1994 of the surface of the resin-coated carrier is 0.01 μm or more and 0.20 μm or less.

Process cartridge and image forming apparatus

A process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus. The cartridge includes an electrophotographic photosensitive drum, a developing roller, a drum unit containing the drum, a developing unit containing the roller and being movable so the roller contacts and is spaced from the drum, and a first force receiver receiving a force from a main-assembly first force applier by movement of a door from open to closed positions when mounting the cartridge and a second force receiver movable from a stand-by position by movement of the first force receiver by a force received from the first force applier. The second force receiver takes a projected position receiving a force from the second force applier to move the developing unit so the roller moves out of contact with the drum, the projected position being higher than the stand-by position.

ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS
20210302847 · 2021-09-30 ·

A cylindrical electrophotographic photosensitive member having concave portions on a surface thereof includes a region A having concave portions at an end portion in an axial direction of the photosensitive member and a region B having concave portions different from those in the region A in a direction toward a center of the axial direction of the photosensitive member from the region A, wherein in the region A, an average value L1 is 20 to 200 μm, an average value W1 satisfies W1≤L1, an average value d1 is 1.7 to 4.0 μm, and an area ratio a1 is 5 to 65%; and in the region B, an average value L2 is 20 to 200 μm, an average value W2 satisfies W2≤L2, an average value d2 is 0.3 to 1.5 μm, and an area ratio a2 is 5 to 65%.

PROCESS CARTRIDGE AND IMAGE FORMING APPARATUS

A process cartridge is detachably mountable to a main assembly of an electrophotographic image forming apparatus. The cartridge includes an electrophotographic photosensitive drum, a developing roller, a drum unit containing the drum, a developing unit containing the roller and being movable so the roller contacts and is spaced from the drum, and a first force receiver receiving a force from a main-assembly first force applier by movement of a door from open to closed positions when mounting the cartridge and a second force receiver movable from a stand-by position by movement of the first force receiver by a force received from the first force applier. The second force receiver takes a projected position receiving a force from the second force applier to move the developing unit so the roller moves out of contact with the drum, the projected position being higher than the stand-by position.