G03G5/10

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus
11726414 · 2023-08-15 · ·

An electrophotographic photosensitive member capable of maintaining a charging ability during repeated use is provided. An electrophotographic photosensitive member having a support, a conductive layer, a photosensitive layer and a protective layer in this order, wherein the protective layer contains a binding resin and a metal oxide particle, the metal oxide particle has a core and a coating layer, the core and the coating layer each contain titanium oxide, and the coating layer further includes niobium.

BASE MATERIAL FOR ELECTROPHOTOGRAPHIC PHOTORECEPTOR, ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS

A base material for an electrophotographic photoreceptor, in which in a spectrum of a period and an amplitude obtained by performing fast Fourier transform of surface roughness of a 10 mm portion in an axial direction of a surface of the base material for an electrophotographic photoreceptor, an amplitude in a range of a period of 0.4 mm or more and 0.7 mm or less is 0.22 mm or less.

Electrophotographic photoreceptor and image forming apparatus
11188003 · 2021-11-30 · ·

An electrophotographic photoreceptor includes a cylindrical substrate; and a surface layer located on an outer surface of the cylindrical substrate. At least a substrate central portion in a cylindrical axial direction of the outer surface of the cylindrical substrate is formed as a rough surface, and a surface roughness of a surface-layer central portion in the cylindrical axial direction of an outer surface of the surface layer is larger than that of at least one of two surface-layer end portions in the cylindrical axial direction of the outer surface of the surface layer. An image forming apparatus includes the electrophotographic photoreceptor; and a peripheral member capable of contacting a surface of the electrophotographic photoreceptor.

Electrophotographic photoreceptor and image forming apparatus
11188003 · 2021-11-30 · ·

An electrophotographic photoreceptor includes a cylindrical substrate; and a surface layer located on an outer surface of the cylindrical substrate. At least a substrate central portion in a cylindrical axial direction of the outer surface of the cylindrical substrate is formed as a rough surface, and a surface roughness of a surface-layer central portion in the cylindrical axial direction of an outer surface of the surface layer is larger than that of at least one of two surface-layer end portions in the cylindrical axial direction of the outer surface of the surface layer. An image forming apparatus includes the electrophotographic photoreceptor; and a peripheral member capable of contacting a surface of the electrophotographic photoreceptor.

SHAPED CHARGE GENERATION LAYER FOR A PHOTOCONDUCTIVE DRUM

A photoconductive drum includes an elongated support element with a shaped charge generation layer. The layer extends from the support element at a single thickness along about two-thirds of a length thereof. Thicker charge generation portions provides denser optical densities compared to thinner portions allowing tailoring the photoconductive drum to compensate for imperfect optical scanning systems. A charge transport layer overcoats the charge generation layer. Optionally, an oxidation layer underlies the charge generation layer as does a protective overcoat overlying the charge transport layer.

ELECTROPHOTOGRAPHIC ELECTRO-CONDUCTIVE MEMBER, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS

Provided an electrophotographic electro-conductive member that can stably suppress an occurrence of fogging in an electrophotographic image. The member comprises a support having an electro-conductive outer surface, and an electro-conductive layer on the outer surface of the support, the electro-conductive layer having a matrix including a cross-linked product of a first rubber, and domains dispersed in the matrix, the domains each includes a cross-linked product of a second rubber and an electro-conductive particle, at least some of the domains is exposed to the outer surface of the electro-conductive member to constitute protrusions on an outer surface of the member, the outer surface of the electro-conductive member is constituted by the matrix and the domains exposed to the outer surface of the electrophotographic electro-conductive member, the electrophotographic electro-conductive member has an impedance of 1.0×10.sup.3Ω or more and 1.0×10.sup.8Ω or less, and some of the domains satisfy two specific requirements.

Electrophotographic electro-conductive member, process cartridge, and electrophotographic image forming apparatus

Provided an electrophotographic electro-conductive member that can stably suppress an occurrence of fogging in an electrophotographic image. The member comprises a support having an electro-conductive outer surface, and an electro-conductive layer on the outer surface of the support, the electro-conductive layer having a matrix including a cross-linked product of a first rubber, and domains dispersed in the matrix, the domains each includes a cross-linked product of a second rubber and an electro-conductive particle, at least some of the domains is exposed to the outer surface of the electro-conductive member to constitute protrusions on an outer surface of the member, the outer surface of the electro-conductive member is constituted by the matrix and the domains exposed to the outer surface of the electrophotographic electro-conductive member, the electrophotographic electro-conductive member has an impedance of 1.0×10.sup.3Ω or more and 1.0×10.sup.8Ω or less, and some of the domains satisfy two specific requirements.

SUPPORT FOR ELECTROPHOTOGRAPHIC PHOTORECEPTOR, ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PHOTORECEPTOR UNIT, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
20230288825 · 2023-09-14 · ·

A support for an electrophotographic photoreceptor includes a cylindrical body having an inner diameter at each of both end parts in an axial direction larger than an inner diameter at a central part in the axial direction, the cylindrical body having a stepped part between the inner diameter at each of the both end parts in the axial direction and the inner diameter at the central part in the axial direction, wherein a coaxiality C between an outer diameter of the cylindrical body and the inner diameter at the central part in the axial direction is 0.3 mm or less.

ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC APPARATUS

Provided is an electrophotographic photosensitive member including: a support having a cylindrical shape; and a photosensitive layer, wherein the support has a surface formed of Al and/or an Al alloy, the surface of the support includes Al crystal grains having: (α) a plane at −15° or more and less than +15° with respect to a {001} orientation; (β) a plane at −15° or more and less than +15° with respect to a {101} orientation; and (γ) a plane at −15° or more and less than +15° with respect to a {111} orientation, a ratio of an area occupied by the Al crystal grain having the (β) to a total area of the surface of the support is 10% or less, and a ratio of an area occupied by the Al crystal grain having the (γ) to the total area of the surface of the support is more than 10%.

ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC APPARATUS

The electrophotographic photosensitive member includes: a support; and a photosensitive layer, wherein a surface of the support is formed of Al and/or an Al alloy, wherein the surface of the support includes Al crystal grains having: (α) a plane at −15° or more and less than +15° with respect to a {001} orientation; (β) a plane at −15° or more and less than +15° with respect to a {101} orientation; and (γ) a plane at −15° or more and less than +15° with respect to a {111} orientation, and wherein a ratio of an area occupied by Al crystal grains each having the (γ) to a total area of the surface of the support is more than 10% and 50% or less, and a ratio of an area occupied by Al crystal grains each having the (α) or the (β) to the remaining area is 80% or more.