G03G5/14795

ELECTROPHOTOGRAPHIC PHOTORECEPTOR, ELECTROPHOTOGRAPHIC PHOTORECEPTOR CARTRIDGE, AND IMAGE FORMING DEVICE
20230273535 · 2023-08-31 · ·

As an electrophotographic photoreceptor including a protective layer (an outermost layer), a photosensitive layer and a conductive support, wherein the protective layer (the outermost layer) comprises a polymer obtained by polymerizing a compound having a chain polymerizable functional group, and the photosensitive layer comprises a hole transport material satisfying the following formula (1) and an electron transport material satisfying the following formula (2):


600≤a  (1)


400≤b  (2) in the formula (1), a represents a molecular weight of the hole transport material, and in the formula (2), b represents a molecular weight of the electron transport material.

ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS

An electrophotographic photosensitive member includes a conductive support having a thickness of 3 mm or more, a photosensitive layer disposed on the conductive support, and a surface protection layer disposed on the photosensitive layer, in which the surface protection layer is a layer composed of a film formed by curing a composition including a reactive group-containing charge transporting material including a reactive group and a charge transporting skeleton in the same molecule, or a film formed by curing a composition including an unreactive charge transporting material and a reactive group-containing non-charge transporting material that does not include a charge transporting skeleton and includes a reactive group, and the ratio of the degree of cure of the conductive support-side surface of the surface protection layer which faces the conductive support to the degree of cure of the outer periphery-side surface of the surface protection layer which serves as the outer periphery is 75% or more.

ELECTROPHOTOGRAPHIC PHOTORECEPTOR, CARTRIDGE USING SAME, AND IMAGE FORMING DEVICE

There is provided an electrophotographic photoreceptor including: a conductive support; and a photosensitive layer and a protective layer containing a cured product obtained by curing a curable compound, which are sequentially disposed on the conductive support. An area ratio A/B is 0.0045 or less, where A is an absorbance area at a wavelength of 1647 cm.sup.−1 to 1627 cm.sup.−1 and B is an absorbance area of a peak at a wavelength of 1800 cm.sup.−1 to 1647 cm.sup.−1 in an infrared absorption spectrum measurement of the protective layer. The photosensitive layer contains at least a hole transport material (HTM) and a radical acceptor compound. The electrophotographic photoreceptor is an electrophotographic photoreceptor including a protective layer with a high curing degree and having good initial electrical characteristics, excellent strong exposure characteristics, and excellent transfer repeatability.

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

The present disclosure provides an electrophotographic photosensitive member having a surface layer in which an occurrence of the image deletion is suppressed; a process cartridge equipped with the electrophotographic photosensitive member; and an electrophotographic apparatus provided with the process cartridge. An electrophotographic photosensitive member has a surface layer that includes a copolymerized product of a composition including a metal oxide particle having a polymerizable functional group on a surface thereof and a polymerizable compound having a particular structure.

Method for producing electrophotographic photosensitive member

A method for producing an electrophotographic photosensitive member including: forming a photosensitive layer; and forming a protective layer, wherein the step of forming the photosensitive layer forms a photosensitive layer having an amount of residual solvent of a first solvent in the photosensitive layer of 0.05% to 2.50% and an amount of residual solvent of a second solvent in the photosensitive layer of 0.50% to 2.50%, and the step of forming the protective layer includes step (A) of forming a cured film and step (B) of forming the protective layer having wrinkle shapes, wherein, in step (A), the irradiated coating film is heated at a heating temperature lower than a boiling point of the first solvent and in step (B), the cured film is heated at a heating temperature higher than a boiling point of the first solvent.

Electrophotographic image forming apparatus and process cartridge

An electrophotographic image forming apparatus in which streak-like banding to be formed in an electrophotographic photosensitive member is suppressed. The electrophotographic image forming apparatus includes an electrophotographic photosensitive member, which has a protective layer, and a developer carrying member for supplying a developer. The protective layer contains a cured product containing an aromatic ring and an ester group, by attenuated total reflection Fourier transform infrared spectroscopy, when a peak area based on C═C stretching vibration of the aromatic ring is represented by S1, and a peak area based on C═O stretching vibration of the ester group is represented by S2, an area ratio S1/S2 is 0.10 to 0.27, and a rotation speed ratio D1/D2 of a rotation speed D1 of the developer carrying member to a rotation speed D2 of the electrophotographic photosensitive member is 0.80 to 1.20.

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 having outer surface with first and second structure groups, the first structure group having a smaller appearance period and a lower height than the second structure group

Provided is an electrophotographic photosensitive drum that achieves both of a reduction in torque of the electrophotographic photosensitive drum at the time of its cleaning and an improvement in image transferability. The electrophotographic photosensitive drum includes: a support; and a photosensitive layer arranged on the support, the electrophotographic photosensitive drum having arranged on an outer surface thereof at least two structure groups having different appearance periods, wherein when, out of the two structure groups, a group including structures having a smaller appearance period is defined as a first structure group, and a group including structures having a larger appearance period is defined as a second structure group, a height of the first structure group is lower than a height of the second structure group.

ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE
20220276580 · 2022-09-01 ·

An electrophotographic image forming apparatus in which streak-like banding to be formed in an electrophotographic photosensitive member is suppressed. The electrophotographic image forming apparatus comprises an electrophotographic photosensitive member, which has a protective layer, and a developer carrying member for supplying a developer. The protective layer contains a cured product containing an aromatic ring and an ester group, by attenuated total reflection Fourier transform infrared spectroscopy, when a peak area based on C═C stretching vibration of the aromatic ring is represented by S1, and a peak area based on C═O stretching vibration of the ester group is represented by S2, an area ratio S1/S2 is 0.10 to 0.27, and a rotation speed ratio D1/D2 of a rotation speed D1 of the developer carrying member to a rotation speed D2 of the electrophotographic photosensitive member is 0.80 to 1.20.

Image forming method and image forming system
11415904 · 2022-08-16 · ·

Provided is an image forming method using a toner for developing an electrostatic charge image and an electrophotographic photoreceptor, and containing at least a charging step, an exposing step, a developing step and a transferring step, wherein the electrophotographic photoreceptor has a photosensitive layer, and the photosensitive layer contains a triphenylamine derivative having a specific structure as a charge transport material, and the toner for developing an electrostatic charge image contains at least titanic acid compound particles as an external additive.