G03G5/06142

ELECTROPHOTOGRAPHIC PHOTORECEPTOR AND IMAGE FORMATION DEVICE
20170371254 · 2017-12-28 · ·

An electrophotographic photoreceptor comprising at least a photosensitive layer on a conductive substrate, wherein the photosensitive layer is a laminate having a charge transport layer and a charge generation layer, the charge transport layer contains four or more types of compounds each having a maximum absorption wavelength falling within a wavelength range of from 300 nm to 600 nm in a tetrahydrofuran solution at 25° C., and maximum absorption wavelengths falling within the wavelength range of at least four types of the compounds of said four or more types of the compounds are separated from each other by 10 nm or more.

ELECTROPHOTOGRAPHIC IMAGE FORMING SYSTEM

An electrophotographic image forming system forms an electrostatic latent image on at least a photoreceptor, develops an image using an electrostatic charge image developing toner, and removes the toner using a cleaning blade. A tip ridge of the cleaning blade is pressed against a surface of the photoreceptor. The system includes a photosensitive layer of the photoreceptor and a surface protecting layer that is provided on a surface of the photosensitive layer. The surface protecting layer includes a polymerizable monomer having at least two polymerizable groups in a molecule and a polymer of a hole transporting compound having a polymerizable group represented by General formula (1). The tip ridge of the cleaning blade has an edge angle that is obtuse and less than 120° and is pressed against the surface of the photoreceptor at an effective contact angle that is in a range of 8 to 20°.

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IMAGE FORMING METHOD AND IMAGE FORMING SYSTEM
20220057724 · 2022-02-24 ·

Provided is an image forming method using an electrophotographic photoreceptor and a toner for developing an electrostatic charge image, and including at least a charging step, an exposure step, a developing step, and a transfer step, wherein the electrophotographic photoreceptor has a photosensitive layer, and the photosensitive layer contains a compound having a structure represented by the following Formula (1) or Formula (2); and in the developing step, the toner for developing an electrostatic charge image containing titanic acid compound particles doped with at least lanthanum as an external additive is used,

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ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
20170248855 · 2017-08-31 · ·

An electrophotographic photoreceptor includes a conductive substrate and a single-layer photosensitive layer on the conductive substrate. The photosensitive layer includes a binder resin, at least one selected from a hydroxygallium phthalocyanine pigment and a chlorogallium phthalocyanine pigment, a hole transporting material, and an electron transporting material and has a Martens hardness Hm of 170 N/mm.sup.2 or more and 200 N/mm.sup.2 or less.

Electrophotographic photosensitive member, process cartridge, and image forming apparatus

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a binder resin, a hole transport material, and an electron transport material. The binder resin includes a polyester resin. The polyester resin includes a first repeating unit represented by general formula (1) shown below and a second repeating unit represented by general formula (2) shown below. ##STR00001##
A content percentage of the polyester resin in the photosensitive layer is at least 0.3% by mass and no greater than 7.0% by mass.

Electrophotographic photoreceptor, process cartridge, and image forming apparatus

An electrophotographic photoreceptor includes a conductive substrate, an organic photosensitive layer on the conductive substrate, and an inorganic protective layer on the organic photosensitive layer. A layer that constitutes a surface of the organic photosensitive layer contains a charge transport material, a binder resin, silica particles, and a silicone compound.

Compound, electrophotographic photoreceptor, and process cartridge
09772567 · 2017-09-26 · ·

A compound has a structure represented by the following formula (C1): ##STR00001##
wherein R.sub.a1, R.sub.a2, R.sub.a3, R.sub.a41, R.sub.a42, R.sub.a43, R.sub.a44, R.sub.a45, R.sub.a5, R.sub.a6, R.sub.a7, R.sub.a8, R.sub.a9, R.sub.a10, and R.sub.a11 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an aralkyl group, an aryl group, a cyano group, a halogen atom, or a group obtained by combining two or more of the above groups, and a combination of R.sub.a1 and R.sub.a2, R.sub.a41 and R.sub.a42, R.sub.a42 and R.sub.a43, R.sub.a43 and R.sub.a44, R.sub.a44 and R.sub.a45, R.sub.a5 and R.sub.a6, R.sub.a8 and R.sub.a9, or R.sub.a10 and R.sub.a11 each independently may form a ring.

Electrophotographic photosensitive member, process cartridge, and image forming apparatus

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer of a single layer. The photosensitive layer contains a charge generating material, a binder resin, a hole transport material, and an electron transport material. The binder resin includes a polyester resin and a polycarbonate resin. The polyester resin includes a first repeating unit represented by general formula (1) shown below and a second repeating unit represented by general formula (2) shown below. The polycarbonate resin includes a third repeating unit represented by general formula (3) shown below and a fourth repeating unit represented by general formula (24) shown below. ##STR00001##
A content percentage of the polyester resin in the photosensitive layer is at least 0.3% by mass and no greater than 7.0% by mass.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

Provided is an electrophotographic photosensitive member including a support and a surface layer, wherein the surface layer contains a copolymer of a composition containing a specific hole transporting compound and a specific compound.

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.