Canon Kabushiki Kaisha

Canon Kasei Kabushiki Kaisha

Seiji Tsuru

Hiroshi Inoue

Satoru Yamada

Kazuhiro Yamauchi

Norifumi Muranaka

Minoru Nakamura

Yuka Hirakoso

Ryo Sugiyama

Tomohito Taniguchi

Kazuaki Nagaoka

Noriaki Kuroda

Noriyuki Doi

Toshihiro Otaka

Yuka Muranaka

Atsushi Ikeda

Hiroaki Komatsu

Shinji Doi

Takashi Koyanagi

Hisao Kato

Hiroyuki Osada

Yuto Miyauchi

Ryosuke Takayama

Koji Yatsu

Atsushi c/o Canon Kasei Kabushiki Kaisha Ikeda

Toshihiro c/o Canon Kasei Kabushiki Kaisha Otaka

An electrophotographic roller comprising a substrate and a foam layer on an outer peripheral surface of the substrate, the foam layer constituting an outer surface of the electrophotographic roller, the foam layer comprising cells each of which opens on the outer surface, and the foam layer having a zero-point charge measured using a standard carrier of 40 μC/g or more.

Electrophotographic roller, process cartridge and electrophotographic image forming apparatus

Provided is such a conductive member that a change in its electrical resistance value caused by its long-term use is reduced to the extent possible. The conductive member has a conductive support and a conductive layer, the conductive layer contains a rubber composition formed of a modified epichlorohydrin rubber, and the modified epichlorohydrin rubber has a unit represented by the following formula (1). In the formula (1), R1, R2, and R3 each independently represent hydrogen or a saturated hydrocarbon group having 1 to 18 carbon atoms. 

Conductive member

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

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

Provided is an electroconductive member that can demonstrate stable performance for a long period of time with an electric resistance value being hardly changed even by electrical conduction for a long period of time. An electroconductive member has a conductive mandrel, and a conductive layer provided on the outer periphery of the conductive mandrel. The conductive layer includes an organic polymeric compound as a binder, and a conductive particle dispersed in the organic polymeric compound, and the particle includes an organic-inorganic hybrid polymer having a specific structure.

Electroconductive member, process cartridge and electrophotographic image forming apparatus

An electroconductive member excellent in durability even when applying direct current voltage over a long period of time is provided. Disclosed is an electroconductive member including an electroconductive mandrel and an electroconductive layer, wherein: the electroconductive layer includes a binder resin and an electroconductive metal oxide particle dispersed in the electroconductive layer; the metal oxide particle has a group represented by the following structural formula (1) on the surface of the metal oxide particle; and the group represented by the following structural formula (1) is introduced by substituting a hydrogen atom of a hydroxyl group as a functional group originating from the metal oxide particle, with the group represented by the following structural formula (1):&#x2014;R&#x2014;SOH.

Electroconductive member, process cartridge and electrophotographic apparatus

Provided is the following electro-conductive member for electrophotography. The electrical resistance of the member hardly increases even by long-term energization, and hence the member is conducive to stable formation of high-quality electrophotographic images. The electro-conductive member for electrophotography, comprises: an electro-conductive mandrel and an electro-conductive layer, wherein said electro-conductive layer contains an A-B-A type triblock copolymer in which an A-block is a polystyrene having a cation exchange group, and a B-block is a polyolefin, and wherein said A-B-A type triblock copolymer forms a microphase-separated structure comprising a matrix phase formed of said B-block, and one phase formed of the A-block and having a structure selected from the group consisting of a cylindrical structure, a bicontinuous structure and a lamellar structure.

Electro-conductive member for electrophotography, process cartridge, and electrophotographic apparatus

In a charging member having a support and one or more cover layer(s), the ten-point average surface roughness of the surface of the charging member, the height of a hill of the surface of the charging member, the area at the part of the hill, and the area of a region surrounded by hills each having the height H (&#x3bc;m) and other hills each having a height of not less than the height H (&#x3bc;m), and not including any hills having a height of more than 0.5H (&#x3bc;m) satisfy a specific relationship. Also, a surface layer of the charging member contains high-molecular compound particles whose average particle diameter is between 2 and 50 &#x3bc;m and whose range of particle size distribution of average particle diameter is above 0&#x3bc;m and not greater than 7 &#x3bc;m.

Charging member, process cartridge, and electrophotographic apparatus

In a conductive member having a support and provided thereon at least one cover layer, the cover layer has a surface layer, and the surface layer contains fine particles. In the surface layer, fine particles present at the surface-layer lower part corresponding to a range within 30% of the total layer thickness from the lowermost plane have an average particle diameter which is larger than the average particle diameter of fine particles present at the surface-layer upper part corresponding to a range within 30% of the total layer thickness from the uppermost plane. A process cartridge and an electrophotographic apparatus have such a conductive member.

Growing community of inventors

Susono, Japan

Seiji Tsuru