Patent classifications
G03G21/1803
Toner, image forming method, image forming apparatus, and process cartridge
Provided is a toner including a binder resin, a release agent, and a charge-controlling agent, wherein the toner includes toner particles having particle diameters of 3 micrometers or smaller, among the toner particles having particle diameters of 3 micrometers or smaller, a proportion of the toner particles having an average circularity of 0.70 or greater but 0.85 or less in all of the toner particles is 10% by number or greater but less than 20% by number and a proportion of the toner particles having an average circularity of less than 0.70 in all of the toner particles is 10% by number or less.
Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
The electrophotographic photosensitive member includes: a support; a charge-generating layer; and a charge-transporting layer, the charge-generating layer and the charge-transporting layer being arranged on the support, wherein a surface layer of the electrophotographic photosensitive member contains: inorganic particles having an average particle diameter (Lα) of primary particles of 5 nm or more and 50 nm or less; and resin particles having an average particle diameter (Lβ) of primary particles of 0.1 μm or more and 5.0 μm or less, and wherein in any cross-section of the surface layer, “(Smα)/(Sα)≥0.3” is satisfied, where a region within (Lβ/2) from a surface of each of the resin particles is defined as a region (M), a sum of cross-sectional areas of the inorganic particles in the any cross-section is represented by (Sα), and a sum of cross-sectional areas of the inorganic particles that are included in the region (M) is represented by (Smα).
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 fluorine-containing resin particles and a fluorine-containing graft polymer having a fluorinated alkyl group. In an infrared absorption spectrum of the fluorine-containing graft polymer, a ratio of a peak area in a wavenumber range of from 1,020 cm.sup.−1 to 1,308 cm.sup.−1 to a peak area in a wavenumber range of from 1,673 cm.sup.−1 to 1,779 cm.sup.−1 is 2.7 or more and 4.8 or less.
Image forming apparatus including drum cartridge attachable to drawer and pressing member for pressing drum cartridge attached to drawer downward
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.
ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
An electrophotographic photoreceptor includes a conductive substrate and a photosensitive layer on the conductive substrate. The outermost surface layer of the electrophotographic photoreceptor contains fluorine-containing resin particles, a fluorine graft polymer, and an acidic compound having an acid dissociation constant (pKa) of 3 or less in water at 25° C. The amount of the acidic compound relative to the outermost surface layer is 100 ppm or more and 10000 ppm or less.
Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus
An electrophotographic photosensitive member including: a support; and a surface layer, wherein the surface layer contains a cured product of a composition containing a curable hole-transport compound, a specific fluorine-atom-containing compound, and a specific polymerizable compound.
IMAGE FORMING APPARATUS INCLUDING DRUM CARTRIDGE ATTACHABLE TO DRAWER AND PRESSING MEMBER FOR PRESSING DRUM CARTRIDGE ATTACHED TO DRAWER DOWNWARD
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 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.
PROCESS CARTRIDGE AND IMAGE FORMING APPARATUS
A process cartridge includes a photosensitive drum and a first casing rotatably supporting the photosensitive drum. The process cartridge also includes a developing roller configured to develop an electrostatic latent image formed on the photosensitive drum with toner, a supplying roller configured to supply the developing roller with the toner, and a second casing rotatably supporting the developing roller and the supplying roller and containing the toner. A rotatable coupling is provided with a projection and operatively connected to the supplying roller and the developing roller so that the coupling can transmit a rotational force to the supplying roller and the developing roller, and at least a part of the coupling being movable in a direction perpendicular to a rotational axis of the coupling. Rotatable gears are configured to transmit the rotational force from the coupling to the developing roller, and a spring urges the at least part of the coupling toward the first casing in the direction perpendicular to the rotational axis of the coupling.
Electrophotographic photosensitive member, process cartridge, and image forming apparatus
An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The hole transport material includes a compound represented by chemical formula (1-1) or (1-2). The photosensitive layer further contains an n-type pigment. The n-type pigment is preferably an azo pigment or a perylene pigment. ##STR00001##