Canon Kabushiki Kaisha

Tomoya Uesugi

Minoru Ito

Kazuhito Wakabayashi

Masaki Yamada

Kazutoshi Ishida

Toru Ishii

Ryo Sugiyama

Kazuaki Nagaoka

Takashi Matsui

Michihisa Magome

Kenta Matsunaga

Yoshinobu Ogawa

Masashi Uno

Wataru Moriai

Akio Nishi

Masamichi Sato

Minoru Nakamura

Masatake Tanaka

Kentaro Yamawaki

Hideya Arimura

Hidenori Satoh

Shintaro Kawaguchi

Fumihiko Utsuno

A process cartridge includes a photosensitive member, a toner, and a developing roller, a surface layer of the photosensitive member has a Martens hardness of 245 to 300 N/mm, the developing roller has a single-layered surface layer containing a substrate and a binder resin; when an elastic modulus of the binder resin in a first region is E1, and an elastic modulus of the binder resin in a second region is E2, E1≥200 MPa and 10 MPa≤E2≤150 MPa are satisfied; the elastic modulus in the second region continuously decreases from that in the first region; the toner comprises a toner particle and an external additive A; the external additive A is a silica particle having a major diameter of 40 to 400 nm; and a coverage of the external additive A with respect to surface of the toner particle is 5.0% or more.

Process cartridge

An electrophotographic member includes an electro-conductive substrate, and an elastic layer as a surface layer, the elastic layer constituted by a single-layer, wherein the elastic layer includes a first resin, a second resin and an anion, the first resin is a crosslinked urethane resin, and the crosslinked urethane resin is a resin having a specific cationic structure in the molecule, the second resin is at least one of a crosslinked acrylic resin having an ether bond and a crosslinked epoxy resin having an ether bond, and in a first area of the elastic layer, the first are being from an outer surface of the elastic layer to a depth of 0.1 μm, the first resin and the second resin form an interpenetrating polymer network structure.

Electrophotographic member, process cartridge, and electrophotographic image forming apparatus

Provided is a developing device including: a toner; and a developer carrying member. The developer carrying member includes an electroconductive substrate and a surface layer on the substrate, the surface layer being a single layer and including a matrix containing a crosslinked urethane resin as a binder, wherein E1 &#x2265;200 MPa and 10 MPa&#x2264;E2 &#x2264;100 MPa, where E1 is an elastic modulus of the matrix in a first region from an outer surface of the surface layer to a depth of 0.1 and E2 is an elastic modulus of the matrix in a second region from a depth of 1.0 to 1.1 &#x3bc;m from the outer surface. The toner includes a toner particle containing a binder resin and a colorant and having a Martens hardness of 85 to 1,100 MPa when measured under a condition of a maximum load of 2.0&#xd7;10N.

Developing apparatus, electrophotography process cartridge, and electrophotographic image forming apparatus

The electrophotographic member includes: an electroconductive substrate; and a surface layer having a mono-layer structure, wherein the surface layer has a matrix containing a cross-linked urethane resin as a binder, and when an elastic modulus of the matrix in a first region in a thickness direction from an outer surface of the surface layer to a depth of 0.1 &#x3bc;m from the outer surface of the surface layer is defined as E1, and an elastic modulus of the matrix in a second region in a thickness direction from a depth of 1.0 &#x3bc;m from the outer surface of the surface layer to 1.1 &#x3bc;m from the outer surface of the surface layer is defined as E2, E1 and E2 satisfy the following Expressions (1) and (2), respectively:1&#x2265;200 MPa&#x2003;&#x2003;(1); and10 MPa&#x2264;2&#x2264;100 MPa&#x2003;&#x2003;(2).

Electrophotographic member having a surface layer with a cross-linked urethane resin-containing matrix, process cartridge, and apparatus

A developing roller that suppresses contamination of the surface of a photosensitive member and also obtains a high-quality image. The developing roller includes an electro-conductive substrate, an electro-conductive elastic layer and a surface layer which are stacked in this order, wherein the surface layer has resin particles that are dispersed in a polyurethane matrix, an outer surface of the surface layer has a first protrusion originating in first resin particle and a second protrusion originating in second resin particle, wherein the first resin particle contains polyurethane, an elastic modulus Eof the first resin particle is 100 to 2000 MPa, an elastic modulus Eof the second resin particle is 2 to 50 MPa, a maximum height roughness Rz of the outer surface is 6 to 18 &#x3bc;m, and a peak vertex density Spd is 5.0&#xd7;10to 5.0&#xd7;10(1/mm).

Developing roller, process cartridge and electrophotographic image forming apparatus

The present invention provides an electrophotographic member which can prevent generation of fogging while high quality images can be output during long-term use. The present invention is an electrophotographic member including a substrate, and an outermost layer directly or indirectly on the substrate, wherein the outermost layer contains a compound having at least a Si&#x2014;O&#x2014;Al bond, and the compound has a structural unit represented by Formula (1) and a structural unit represented by AlO. 

Electrophotographic member, developing apparatus and image forming apparatus

The developing apparatus includes a toner, a developing container, a developing roller, and a toner layer thickness controlling member,

Developing apparatus, developing method, image forming apparatus, and image forming method

A developing apparatus and a developing method that significantly suppress generation of fogging and form a high-quality electrophotographic images under any environments such as a high temperature and high humidity environment and a low temperature and low humidity environment are provided. A toner wherein a covering rate X1 of the surface of a toner particle with silica fine particles, which is determined by ESCA, is 40.0 to 75.0 area %, and the diffusion index represented by (Expression 1) diffusion index=X1/X2 satisfies (Expression 2) diffusion index&#x2267;&#x2212;0.0042&#xd7;X1+0.62 where in the theoretical covering rate with the silica fine particles is defined as X2; and a developing apparatus including a developing carrying member which is a surface layer formed of a urethane resin having a partial structure derived from a reaction of a polyisocyanate with a compound represented by Formula 1.

An electrophotographic member whose performances are hardly changed even after a long-term use is provided. An electrophotographic member having a mandrel, an elastic layer and a surface layer, wherein the surface layer contains a titanium oxide film having chemical bonds represented by the following formula (1) and formula (2) is provided.O&#x2014;Ti&#x2014;O&#x2003;&#x2003;Formula (1)Ti&#x2014;O&#x2014;C&#x2003;&#x2003;Formula (2)

Electrophotographic member, process cartridge and electrophotographic apparatus

A high quality electrophotographic member that is excellent in deformation recovery property under high-temperature and high-humidity and that also satisfies filming resistance under low-temperature and low-humidity is provided. The electrophotographic member includes a substrate, an elastic layer, and a surface layer containing a urethane resin, wherein the urethane resin has a partial structure having at least one structure selected from the group consisting of structures of structural formulae (1) to (7) between adjacent two urethane linkages, and the urethane resin further has a partial structure derived from a reaction of a compound represented by a structural formula (8) with a polyisocyanate.

Provided is an electrophotographic member, which hardly changes in performance even when being left to stand for a long time period. The electrophotographic member comprises a support, an elastic layer formed on the support, and a surface layer covering a surface of the elastic layer and containing a urethane resin, and in which the urethane resin comprises a reaction product of: a hydroxyl group-terminated prepolymer obtained by reacting a polyester polyol with a polyisocyanate; and an isocyanate-terminated prepolymer obtained by reacting a polyester polyol with a polyisocyanate.

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Susono, Japan

Tomoya Uesugi