Canon Kabushiki Kaisha

Takashi Koyanagi

Masaki Yamada

Shohei Urushihara

Minoru Nakamura

Kentarou Nakamura

Yuji Sakurai

Kunimasa Kawamura

Sosuke Yamaguchi

Minoru Ito

Hideya Arimura

Takahiro Miyazawa

Takuho Sato

Toru Ishii

Hiroki Tanaka

Kazuhisa Shida

Makoto Fukatsu

Kazuaki Nagaoka

Motonari Ito

Kuniaki Tamagaki

Akihisa Matsukawa

Ryosuke Kanai

Seiji Tsuru

Kineo Takeno

Yuto Miyauchi

Takanori Kaihara

Yuta Isobe

A developing device including: a developer; and a developing member configured to carry the developer on a surface thereof, the developing roller including an electro-conductive substrate and a single-layer elastic layer serving as a surface layer on the substrate, the surface layer comprising a binder resin, and the binder resin contains a crosslinked urethane resin and a crosslinked acrylic resin, the crosslinked urethane resin and the crosslinked acrylic resin form an interpenetrating polymer network structure in a first region from an outer surface of the surface layer to a position at a depth of 0.1 μm from the outer surface, wherein the developer contains developer particles each containing at least a binder resin and a magnetic substance.

Developing device, process cartridge, and electrophotographic image forming apparatus

An image forming apparatus includes a developer carrying member that bears and conveys developer. The developer carrying member has at least a base and a surface layer, with the surface layer having an electron donating portion that mainly donates charge to the developer when the developer and the surface layer make frictional contact to exchange charge and an electron accepting portion that mainly accepts charge from the developer when the developer and the surface layer makes frictional contact to exchange charge. A controller applies an AC voltage to the developer carrying member during a period in which an image forming operation is not performed and the developer carrying member is driven, with the AC voltage being different from that applied during an image forming period, and a rotating speed of the developer carrying member during a non-image forming period is slower than that during an image forming period.

Image forming apparatus having toner charging

An electrophotographic member including an electro-conductive substrate, an elastic layer, and a surface layer, the surface layer containing a fine particle and a binder resin, and having a thickness of less than 1.0 μm, the fine particles having an average particle diameter of from 0.1 μm to 0.9 μm, the fine particles having a volume occupancy of 60 vol % to 99 vol % with respect to 100 vol % of the binder resin in the surface layer, the elastic modulus E1 of the fine particle being 1,000 MPa or more, and the elastic modulus E2 of the binder resin being 2 MPa to 200 MPa, and MD-1 hardness H1 of the surface layer being 50° to 100°, and a difference (H1−H2) between the H1 and MD-1 hardness H2 of the elastic layer being 5° or more.

Electrophotographic member, electrophotographic process cartridge, and electrophotographic image forming apparatus

The developing member includes a substrate having an electroconductive outer surface; an insulating resin layer on the outer surface of the substrate; and electrically insulating domains on an outer surface of insulating resin layer, and has an outer surface including a surface of the insulating resin layer and surfaces of the domains, wherein a potential decay time constant of each of the surfaces of the domains is &#x2265;60.0 seconds, and a potential decay time constant of the surface of the electrically insulating resin layer is &#x3c;6.0 seconds, and assuming that the electrically insulating domains are orthographically projected onto the outer surface of the substrate, to obtain projection images of the respective domains, each of areas of the projection images is defined as S, and each of areas of convex envelopes of the projection images is defined as H, at least one of the domains satisfies 0.05&#x2264;S/H&#x2264;0.80.

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

Provided is a developer carrying member that enables stable formation of images of high quality even on recording paper having a high talc content. The developer carrying member includes a conductive base member and a surface layer, wherein the surface layer includes a urethane resin, and the urethane resin has a carbonate bond and a tertiary amine structure.

Developer carrying member, process cartridge, and electrophotographic apparatus

The developer carrying member, includes: an electroconductive substrate; and a surface layer containing a resin, on the substrate, in which a thickness of the surface layer is 1.0 &#x3bc;m or more and 100.0 &#x3bc;m or less, a Martens hardness at an indentation depth of 0.1 &#x3bc;m that is measured by infiltrating a Vickers indenter in a thickness direction of the surface layer from an outer surface of the surface layer is 50.0 N/mmor more and 100.0 N/mmor less, an Asker C hardness that is measured from the outer surface of the surface layer is 75&#xb0; or more and 90&#xb0; or less, and a value of a work function of the outer surface of the surface layer is 5.6 eV or more and 6.0 eV or less.

The present invention provides an electrophotographic member which has a high ability to impart charge to toners while the charge imparting ability is unlikely to be reduced even under an environment at high temperature and high humidity. The electrophotographic member comprises a substrate, an elastic layer formed on the substrate, an intermediate layer covering the surface of the elastic layer, and a surface layer covering the surface of the intermediate layer, wherein the intermediate layer contains a binder resin and a polymer having a specific structure, the surface layer contains silicon oxide, and the surface layer has a thickness of 10 nm or more and 300 nm or less.

Electrophotographic member, process cartridge and electrophotographic image forming apparatus

Provided is an electrophotographic member which hardly undergoes deformation even when subjected to a load over a long period of time under a high-temperature and high-humidity environment and thus can stably form a high-quality electrophotographic image. The electrophotographic member includes: an electroconductive substrate; and an electroconductive resin layer on the substrate, in which the resin layer contains a cation having a specific structure and a specific anion.

Electrophotographic member, process cartridge, and electrophotographic apparatus

Provided is an electrophotographic member that is excellent in charge-imparting performance for a toner, and that hardly causes tackiness on its surface even when placed under a high-temperature and high-humidity environment over a long time period. The electrophotographic member includes a substrate and a surface layer, in which the surface layer satisfies the following requirements (A) and (B): (A) the surface layer contains, in a region from its surface to a depth of up to 0.1 &#x3bc;m, a copolymer containing a constituent unit represented by the following structural formula (1), and at least one selected from the group consisting of a constituent unit represented by the following structural formula (2) and a constituent unit represented by the following structural formula (3); and (B) the concentration of a nitrogen atom derived from a nitrogen-containing aromatic heterocyclic amine structure in the copolymer is from 6.0 mass % to 30.0 mass %. 

Electrophotographic member, method of producing the same, process cartridge, and electrophotographic apparatus

Provided are a developer carrying member, and a process cartridge and an electrophotographic apparatus using the developer carrying member, the developer carrying member including a substrate, an elastic layer, and a surface layer covering a surface of the elastic layer in which the surface layer contains a modified acrylic resin, and the modified acrylic resin has a constituent unit represented by the following structural formula (1). (R1 represents an alkyl group having 1 to 3 carbon atoms; U represents a urethane resin having, between two adjacent urethane bonds, a structure represented by the following structural formula (2), and at least one of structure selected from a structure represented by the following structural formula (3) and a structure represented by the following structural formula (4); and L represents a divalent linking group containing an ester bond (&#x2014;O&#x2014;C(&#x2550;O)&#x2014;)). 

Developer carrying member, electrophotographic process cartridge, and electrophotographic image forming apparatus

A high quality developing member that is excellent in deformation recovery property under a high temperature and that also satisfies filming resistance under a low temperature is provided. The developing member of the present invention includes a mandrel, an elastic layer formed on the outer periphery surface of the mandrel, and a surface layer covering the outer periphery surface of the elastic layer, wherein the surface layer contains a first resin and a second resin, the first resin has a particular structure between adjacent two urethane linkages, and the second resin is a resin having a particular structure and having a glass transition point Tg of 20&#xb0; C. or higher and 120&#xb0; C. or lower.

Developing member, process cartridge and electrophotographic apparatus

A high-quality developing member which excels in filming resistance and excels in leak resistance despite high electroconductivity is provided. The developing member includes an electroconductive substrate, an elastic layer formed on the substrate, and a surface layer which covers a surface of the elastic layer. The surface layer includes a first resin which has, between two adjacent urethane linkages, a structure represented by the structural formula (1) and one or both of structures selected from the group consisting of a structure represented by the structural formula (2) and a structure represented by the structural formula (3), a second resin which has a structure represented by the structural formula (4) and one or both of structures selected from the group consisting of a structure represented by the structural formula (5) and a structure represented by the structural formula (6), and an electronically conductive filler.

Developing member, process cartridge, and electrophotographic apparatus

A developing roller which is excellent in image quality and image durability and stably outputs a uniform image, and a process cartridge and an electrophotographic apparatus using the developing roller are provided. The developing roller has a mandrel, an elastic layer and a surface layer covering the elastic layer surface, wherein the surface layer contains a urethane resin having at least one structure of the followings A) and B) between two adjacent urethane linkages: A) a structure represented by the following structural formula (1), and at least one structure selected from the group consisting of structures represented by the following structural formulae (2) and (3), and B) a structure represented by the following structural formula (4), and the surface layer contains polyurethane resin particles of which the elastic part of the indentation work based on ISO 14577-1 is 80% or more, is obtained: 

Developer support member, electrophotographic process cartridge and electrophotographic image forming apparatus

Provided is a developing member capable of suppressing a variation in resistance even when exposed to a high-temperature, high-humidity environment for a long time period. The developing member comprises: a mandrel; an electro-conductive elastic layer provided on a periphery of the mandrel; and a surface layer provided on a surface of the elastic layer, wherein: the elastic layer contains a dimethyl silicone rubber and carbon black; and an amount &#x3b1; of a hydrogen atom bound to a silicon atom of the dimethyl silicone rubber, and an amount &#x3b2; of a hydrogen atom of methyl groups bound to a silicon atom of the dimethyl silicone rubber, satisfy a relationship of 2.5&#xd7;10&#x2266;&#x3b1;/&#x3b2;&#x2266;1.0&#xd7;10.

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Mishima, Japan

Takashi Koyanagi