G03G5/104

PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS

A process cartridge which allows any spot and stripe as image defects to be suppressed is provided. A process cartridge, in which an electroconductive layer of a charging member has a matrix including a first rubber, and domains dispersed in the matrix, the domains include a second rubber and an electron electroconductive agent, at least some of the domains are exposed on a surface of the charging member, when a volume resistivity of the matrix is 10.sup.5 times or more a volume resistivity of the domains, a protective layer of an electrophotographic photosensitive member includes a metal oxide particle, and when a number average primary particle size of the metal oxide particle is defined as Sm and an average value of equivalent circle diameters of the domains is defined as Sd, the Sd/Sm satisfies the following expression (1): 0.5<Sd/Sm<100 . . . expression (1).

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

There is provided an electrophotographic photosensitive member that can achieve both of an adequately high initial sensitivity as the electrophotographic photosensitive member and reduction in the fluctuation of a light portion potential at the time of repeated use. An electrophotographic photosensitive member includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a metal oxide particle; the metal oxide particle has a core material containing a titanium oxide, and a covering layer which covers the core material and contains the titanium oxide; and when the oxygen deficiency ratio of the metal oxide particle is represented by A, the oxygen deficiency ratio of the core material is represented by B, and the oxygen deficiency ratio of the covering layer is represented by C, the Expressions (1) and (2) are satisfied: A2% (1) and 10B<C (2).

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

An electrophotographic photosensitive member includes, in sequence, a support, a conductive layer, an undercoat layer, a charge generation layer, and a charge transport layer. The conductive layer is a cured film, and the cured film contains titanium oxide particles doped with niobium. The undercoat layer contains a cured product of a composition that contains an electron transport material having a polymerizable functional group and a resin functionalized with a carboxylic acid derivative.

ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS

The present disclosure provides an electrophotographic photosensitive member that can simultaneously achieve the suppression of the occurrence of the black spot in a charged portion and the suppression of the deterioration in sensitivity of an exposed portion, even after stored in a high-temperature and high-humidity environment. An electrophotographic photosensitive member includes an electro-conductive support, an undercoat layer, a charge generation layer and a charge transport layer in this order, wherein an atomic concentration ratio R of the oxygen atom to the aluminum atom on the surface of the electro-conductive support, as measured by energy dispersive X-ray spectroscopy, satisfies the following Expression (1):


1.6R(1) and the undercoat layer includes a titanium oxide particle that is surface-treated with a particular silane compound.

CONDUCTIVE ROLL FOR ELECTROPHOTOGRAPHIC DEVICE

A conductive roll for electrophotographic device is provided. The conductive roll for electrophotographic device 10 includes a shaft body 12 and a non-foamed elastic body layer 14 formed on an outer periphery of the shaft body 12. The elastic body layer 14 is made of a cross-linked product of a silicone rubber composition containing the following (a) to (d), and a secondary particle diameter of the following (d) in the elastic body layer 14 is within a range of 100 to 500 nm. (a) is an organopolysiloxane, (b) is a crosslinking agent, (c) is a microcapsule catalyst made of fine resin particles which encapsulate a crosslinking catalyst by a resin other than a silicone resin, and (d) is silica with a BET specific surface area of 70 to 350 m.sup.2/g.

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 1.010.sup.3 or more and 1.010.sup.8 or less, and some of the domains satisfy two specific requirements.

ELECTROPHOTOGRAPHIC PHOTORECEPTOR AND IMAGE FORMING APPARATUS
20200257211 · 2020-08-13 · ·

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.

Image forming method and image forming device
10627730 · 2020-04-21 · ·

An image forming method forms an image by performing charging, exposing, developing, and transferring in a rotation direction of a rotationally driven photoreceptor, wherein the charging is performed by a roller charging method, exposing a surface of the photoreceptor to light and eliminating charges on the surface of the photoreceptor are included between the developing and the transferring, the photoreceptor includes at least a charge transporting layer and a protective layer laminated on the charge transporting layer on a conductive support, and energy of light for irradiation in the exposing the surface of the photoreceptor to light is in a range of 0.0001 to 500 W/mm.sup.2 on the surface of the photoreceptor.

ELECTROPHOTOGRAPHIC PHOTORECEPTOR AND IMAGE FORMING APPARATUS
20200081359 · 2020-03-12 · ·

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 PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS

There is provided an electrophotographic photosensitive member that can achieve both of an adequately high initial sensitivity as the electrophotographic photosensitive member and reduction in the fluctuation of a light portion potential at the time of repeated use. An electrophotographic photosensitive member includes a support, an electroconductive layer and a photosensitive layer in this order, wherein the electroconductive layer contains a binder material and a metal oxide particle; the metal oxide particle has a core material containing a titanium oxide, and a covering layer which covers the core material and contains the titanium oxide; and when the oxygen deficiency ratio of the metal oxide particle is represented by A, the oxygen deficiency ratio of the core material is represented by B, and the oxygen deficiency ratio of the covering layer is represented by C, the Expressions (1) and (2) are satisfied: A2% (1) and 10B<C (2).