An electrophotographic photoreceptor includes a conductive substrate, an undercoat layer on the conductive substrate, a charge generation layer on the undercoat layer, a charge transport layer on the charge generation layer, and an inorganic protection layer on the charge transport layer, in which the charge transport layer contains a binder resin and a charge transport material, and, when impedance of the charge transport layer is measured, a ratio (C.sub.1Hz/C.sub.10Hz) of an electrostatic capacitance C.sub.1Hz at 1 Hz to an electrostatic capacitance C.sub.10Hz at 10 Hz is 1.1 or less.

An electrophotographic photoconductor is provided. The electrophotographic photoconductor includes a conductive substrate, a photosensitive layer, and a surface layer containing fluororesin particles, non-fluororesin particles, and a cured resin. The fluororesin particles have an average particle diameter of from 0.01 to 0.3 m in a cross-sectional image of the surface layer as observed by a scanning electron microscope with a magnification of 5,000 times, and when the cross-sectional image is segmented into uniform regions each being 1 m4 m, a standard deviation of areas each of which is occupied by the fluororesin particles and the non-fluororesin particles in each of the regions is 0.2 m.sup.2 or less.

Provided are a process cartridge and an electrophotographic apparatus each suppressed in fluctuation in charging potential at the time of its long-term use. The process cartridge includes: an electrophotographic photosensitive member having a surface layer containing a resin and a charge-transporting substance; and a charging member configured to charge the electrophotographic photosensitive member, wherein an average of Martens hardnesses of the surface layer of the electrophotographic photosensitive member measured at a pushing force of 7 mN is 245 N/mm.sup.2 or more, and wherein in a core defined by three-dimensional surface texture standards (ISO 25178-2:2012) of the surface of the charging member, an average of Martens hardnesses measured at a pushing force of 0.04 mN is 2 N/mm.sup.2 or more and 20 N/mm.sup.2 or less, and an average of adhesivenesses measured with a scanning probe microscope in a field of view of 2-micrometer square is 70 mV or less.

The present invention provides an electrophotographic photoreceptor including a photosensitive layer containing an electron transport material, and having high pressure resistance and suppressed occurrence of a leak phenomenon, a method for producing the same, and an electrophotographic device using the same. The electrophotographic photoreceptor includes an electrically conductive support containing an aluminum alloy; an anodic oxide film formed on a surface of the electrically conductive support; and a photosensitive layer formed on the anodic oxide film. The photosensitive layer contains an electron transport material having an electron mobility of 10.sup.7 cm.sup.2/V/sec or more when field intensity is set to 20 V/m. The surface of the electrically conductive support having the anodic oxide film formed thereon has an admittance value that is 25 S or more and 60 S or less.

To provide a conductive roll for an electrophotographic apparatus that includes a conductive rubber elastic body layer having a lower hardness and lower settling properties than a conventional conductive rubber elastic body layer. A conductive roll 10 for an electrophotographic apparatus includes a shaft body 12, and a conductive rubber elastic body layer 14 provided on the outer periphery of the shaft body 12, the conductive rubber elastic body layer 14 containing polar rubber, non-polar rubber, and a dispersing agent, wherein the polar rubber is at least one of nitrile rubber, hydrin rubber, and chloroprene rubber, wherein the non-polar rubber is at least one of isoprene rubber, hydrogenated isoprene rubber, and natural rubber, and wherein the dispersing agent is at least one of a polymer containing a block made of a nitrile rubber component and a block made of an isoprene rubber component, modified natural rubber, and modified isoprene rubber.

There is provided an electrophotographic member which suppresses scraping and contamination of a surface even in the durable use of multiple sheet printing under a high temperature environment. The electrophotographic member has an electroconductive substrate and a single elastic layer as a surface layer, the surface layer includes a binder resin and carbon black dispersed in the binder resin, the carbon black has a volatile content of 0.4% or more, the binder resin includes a crosslinked urethane resin and a crosslinked acrylic resin, and the surface layer has a first area in which the crosslinked urethane resin and the crosslinked acrylic resin form an interpenetrating polymer network structure, the first area being from an outer surface of the surface layer to a depth of 0.1 m in the surface layer.

A photoreceptor comprises a conductive substrate. An undercoat layer is disposed on the conductive substrate. The undercoat layer includes modified metal oxide particles and a binder resin, the modified metal oxide particles comprising metal oxide particles having an outer surface and hygroscopic polymers attached to the surface. The hygroscopic polymers are made by linking a hydrophilic polymer group to the metal oxide particles using a dithiofunctionalized phosphonatomethylaryl ligand that acts as the linking group. A photosensitive layer is disposed on the undercoat layer.

The present invention relates to an electrophotographic photoreceptor which is a positive charging type electrophotographic photoreceptor comprising a conductive support and a photosensitive layer on the conductive support, wherein the photosensitive layer contains at least a charge generating material, a hole transport material, an electron transport material, and a binder resin in the same layer, and a residual potential VL.sub.1 at a point at which an exposure amount for forming a latent image is 0.3 J/cm.sup.2 is equal to or lower than 130 V when an initial surface potential V0 is set to +700 V, exposure with monochromatic light of 780 nm is performed and measurement is performed by a dynamic method.

An electrophotographic photosensitive member includes a support member, an electroconductive layer, and a photosensitive layer, in this order. The electroconductive layer contains a binder resin, electrically conductive first metal oxide particles, and second metal oxide particles. The refractive index Rb of the binder resin, the refractive index Rc of the first metal oxide particles, and the refractive index Rh of the second metal oxide particles satisfy the relationships: |RbRc|0.35 and |RbRh|0.65. The electroconductive layer has a volume resistivity of 1.010.sup.6 .Math.cm to 1.010.sup.13 .Math.cm, and the ratio of the specific gravity of the first metal oxide particles to the specific gravity of the second metal oxide particles is 0.85 to 1.20.

The present invention relates to a solid lubricant to be coated on an image bearing member included in an electrophotographic image forming apparatus. The solid lubricant contains a resin particle and metal soap. The resin particle includes a particle body containing an amorphous resin as a principal component, and a fluorine atom supported on a surface of the particle body. The resin particle is a particle having a volume average particle size of 70 nm or more. The solid lubricant can sufficiently increase a cleaning effect in the image forming apparatus.