Canon Kabushiki Kaisha

Noriyuki Doi

Kineo Takeno

Masataka Kodama

Hiroki Masu

Noriko Suzumura

Minoru Nakamura

Ryo Sugiyama

Masahiro Kurachi

Noriaki Kuroda

Kenichi Yamauchi

Hiroshi Mayuzumi

Seiji Tsuru

Naoki Yamada

Taichi Sato

Kenta Kamikura

Hajime Miyazaki

Kazuaki Nagaoka

Yuzo Seino

Akira Unno

Naotake Sato

Yusuke Yagisawa

Takuho Sato

A developing apparatus comprising a toner and a toner bearing member for bearing the toner, wherein the volume resistivity of the toner is from 1.0×10Ω·cm to 1.0×10Ω·cm, a toner bearing member exhibits multiple elementary processes, the volume resistance value Rdr per unit area of the toner bearing member is from 5.0×10Ω/cmto 2.0×10Ω/cm, the capacitance Cdr per unit area of the toner bearing member is from 300 pF/cmto 900 pF/cm, and the capacitance per unit area and volume resistance value of the toner as converted by a parallel plate capacitor model at a thickness of 1.5 times the weight-average particle diameter of the toner are in specific relationships.

Developing apparatus

An electrophotographic member has an electro-conductive substrate, an elastic layer on the substrate and a coating layer on the elastic layer. The elastic layer has an elastic modulus of 0.5 MPa to 3.0 MPa and the coating layer has an elastic modulus of 5.0 MPa to 100.0 MPa as measured in an environment of a temperature of 30&#xb0; C. and a relative humidity of 80%.

Electrophotographic member having elastic layer with elastic modulus of 0.5 to 3.0 MPA and coating layer with elastic modulus of 5.0 to 100 MPA

Provided is a developing roller comprising an electroconductive substrate and an electroconductive layer thereon, the electroconductive layer retaining resin particles so that at least a part of each of the resin particles is exposed on an outer surface of the developing roller; the outer surface of the developing roller constituted by electrically insulating domains and an electroconductive matrix, assuming that a square region 200-&#x3bc;m in a side is put on the outer surface of the developing roller, the square region including the domains, among the domains in the square region at least two of them satisfying specific condition, and assuming that the outer surface of the developing roller is charged, and creating a potential map of the charged outer surface of the developing member, the two domains satisfying the specific condition being ascertained in the potential map.

Developing roller, electrophotographic process cartridge and electrophotographic image forming apparatus

A charging member is provided that has high charging ability and can prevent generation of abnormal discharge even under an environment at a low temperature and a low humidity. The charging member includes an electroconductive support, an electroconductive elastic layer and a surface layer. The electroconductive elastic layer contains electrically insulating domains such that at least a part of the electrically insulating domains is exposed on the surface of the electroconductive elastic layer. The surface layer contains a polymetalloxane having a structure represented by Structural Formula (a1), and M1 in Structural Formula (a1) and a carbon atom in a structural unit represented by Structural Formula (a2) are bonded through a linking group represented by Structural Formula (a3). 

Charging member, process cartridge and electrophotographic image forming apparatus

There is provided a charging member exhibiting stable charging performance even after the use for a long period of time. The charging member includes a support and a surface layer on the support, the surface layer includes polymetalloxane containing at least one metal atom selected from the group consisting of aluminum, zirconium, titanium, and tantalum, and a group represented by the following formula (1) or (2) is bonded to at least the one metal atom in the polymetalloxane, wherein X represents an atomic group required for forming a ring, A1 and A2 each independently represent a hydrogen atom or an alkyl group, and a symbol '*' represents a binding site with a metal atom in the polymetalloxane.

Charging member, method for producing charging member, process cartridge and electrophotographic image forming apparatus

A charging member which has high charging ability and prevents generation of abnormal discharge is provided. The charging member includes a support and a surface layer. The surface layer contains a polymetalloxane having a specific structure.

Charging member, process cartridge and electrophotographic apparatus

Provided is a charging member that suppresses the occurrence of abnormal discharge under low temperature and low humidity. The charging member includes a support and a surface layer on the support, and the surface layer contains a compound represented by the following formula (a), (b), (c), or (d). 

Charging member, process cartridge, and electrophotographic image forming apparatus

A charging member is provided which can prevent electrostatic adhesion of a toner and/or an external additive of the toner to the surface of the charging member, and exhibits stable charging performance during long-term use. The charging member comprises a support, and a surface layer on the support, and the surface layer comprises a polymetalloxane containing at least one metal atom selected from the group consisting of aluminum, titanium, zirconium and tantalum, and a specific group which is bonded to the at least one metal atom in the polymetalloxane.

A charging member capable of inhibiting the effect of the contact mark on the electrophotographic image, even after in contact with another member for a long term, is provided. The charging member has a surface layer on a support, the surface layer containing a polymer compound having a structural unit represented by the following formula (1):  In the formula (1), A represents an aromatic cyclic hydrocarbon group; Rrepresents a specific hydrocarbon group. L represents a polysiloxane having at least one of an SiOunit (T) and an SiOunit (D). U represents an integer of 1 or more.

Charging member, process cartridge, and electrophotographic apparatus

There is provided a charging member capable of preventing the occurrence of abnormal discharge at low temperature and low humidity, and capable of preventing the occurrence of an image defect due to abrasion. The charging member includes a support and a surface layer on the support, and the surface layer contains a specific compound.

Provided is a method of producing a member for electrophotography capable of providing a high-quality electrophotographic image. The method of producing a member for electrophotography is a method of producing a member for electrophotography having an electro-conductive support, an elastic layer, and a surface layer, the method comprising: a first step of forming, on a surface of the elastic layer, a coat of a surface-layer coating liquid containing a hydrolyzed condensate of a hydrolyzable silane compound and a chelate titanium compound represented by the following general formula (2); and a second step of crosslinking the hydrolyzed condensate in the coat through cleavage of an epoxy group in the hydrolyzed condensate to form the surface layer: 

Method of producing member for electrophotography

A pyrene compound represented by general formula (1): 

Pyrene compound and organic electroluminescent device including the same

There is provided a charging member having charging performance that is not easily changed even by long-term use. The charging member includes an electro-conductive support, an elastic layer, and a surface layer. The elastic layer contains particles in such a manner that at least a part of the particles are exposed from the elastic layer, and thus a surface of the elastic layer is roughened. The particles are high-molecular-weight polyethylene particles. The surface of the elastic layer is covered with the surface layer in such a manner that the surface shape of the elastic layer is reflected in the surface shape of the charging member. The surface layer contains a high-molecular compound having a specific constitutional unit.

Charging member and electrophotographic apparatus

Disclosed are an organic semiconductor material including a thiazole compound represented by the following general formula (1) and an organic thin-film transistor using the organic semiconductor material:A1-B1-C1&#x2003;&#x2003;(1)wherein A1 and C1 each represent an unsubstituted or substituted thiazole ring, and B1 represents an unsubstituted or substituted benzene ring or an unsubstituted or substituted polycondensed aromatic ring. Accordingly, there are provided an organic semiconductor material having high ON current and excellent storage stability and an organic thin-film transistor using the organic semiconductor material.

Organic semiconductor material and organic thin-film transistor

Provided are a compound represented by the following general formula (1):A-B-X-C-D

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Numazu, Japan

Noriyuki Doi