Canon Kabushiki Kaisha

Takumi Furukawa

Hiroaki Watanabe

Kenya Terada

Yuya Tomomizu

Kazuhiro Yamauchi

Yuichi Kikuchi

Kenji Takashima

Satoru Nishioka

Masahiro Kurachi

Toshimitsu Nakazawa

Toshiro Suzuki

Masaaki Harada

Keiji Nose

Masaki Yamada

Kana Sato

Kazuhiro Gesho

Jun Murata

Tetsuo Hino

Noriaki Kuroda

Toshinari Miura

Hisao Kato

Yukinori Nagata

Yoko Kuruma

Yusuke Yagisawa

Yasuhiro Fushimoto

Kenichi Yazawa

Masaki Ozawa

Michitaka Kitahara

Kazuyuki Shishitsuka

Harunobu Ogaki

Kazunori Noguchi

Daisuke Miura

Hidekazu Matsuda

Tomohito Taniguchi

Takashi Hiramatsu

Hiroshi Inoue

Shinji Katagiri

Shuichi Tetsuno

Tsuguhiro Yoshida

Takayuki Tanaka

Taichi Sato

Tatsuya Yamaai

Shuhei Iwasaki

Akira Sakakibara

Takayuki Namiki

Takahiro Ikeda

Satoru Motohashi

Shuhei Tokiwa

Norifumi Muranaka

Takashi Mukai

Masafumi Kyogaku

Atsushi Uematsu

Hiroki Masu

Masaki Tsunoda

Provided is an electrophotographic electroconductive member, including: an electroconductive support; an electroconductive layer; and a surface layer in order, wherein an impedance is 1.0×10Ω to 1.0×10Ω at an outer surface of the electroconductive member, in the surface layer, an electronic electroconductive agent is dispersed, the electroconductive layer has a matrix containing a cross-linked product of a first rubber and domains each containing a cross-linked product of a second rubber and electroconductive particles, and wherein, and wherein among the domains observed in specified observation regions, 80% by number or more of the domains satisfy (1) and (2):

Electroconductive member, process cartridge, and electrophotographic image formation device

Provided an electrophotographic electro-conductive member that can stably suppress an occurrence of fogging in an electrophotographic image. The member comprises a support having an electro-conductive outer surface, and an electro-conductive layer on the outer surface of the support, the electro-conductive layer having a matrix including a cross-linked product of a first rubber, and domains dispersed in the matrix, the domains each includes a cross-linked product of a second rubber and an electro-conductive particle, at least some of the domains is exposed to the outer surface of the electro-conductive member to constitute protrusions on an outer surface of the member, the outer surface of the electro-conductive member is constituted by the matrix and the domains exposed to the outer surface of the electrophotographic electro-conductive member, the electrophotographic electro-conductive member has an impedance of 1.0×10Ω or more and 1.0×10Ω or less, and some of the domains satisfy two specific requirements.

Electrophotographic electro-conductive member, process cartridge, and electrophotographic image forming apparatus

Provided is an electrophotographic electroconductive member including an electroconductive support and an electroconductive layer on the support, an electroconductive member is used, in which an electroconductive layer has a matrix comprising a first rubber, and domains dispersed in the matrix, the domains each comprising a second rubber and an electronic electroconductive agent, and for impedance measured by applying an AC voltage with an amplitude of 1 V to the electroconductive layer while varying frequencies between 1.0&#xd7;10Hz to 1.0&#xd7;10Hz under a specific environment, when a double logarithmic plot with a frequency on an abscissa and an impedance on an ordinate is obtained, a slope on a high frequency side is &#x2212;0.8 or more and &#x2014;0.3 or less, and the impedance a low frequency side is from 1.0&#xd7;10to 1.0&#xd7;10&#x3a9;.

Electroconductive member, process cartridge, and image forming apparatus

The electro-conductive member has an electro-conductive support, and an electro-conductive layer, in which the electro-conductive layer has a matrix including a first rubber cross-linked product and domains dispersed in the matrix, each of the domains includes a second rubber cross-linked product and electro-conductive particles, an outer surface of the electro-conductive member has concave portions, a surface of at least a part of the domains is exposed to the outer surface of the electro-conductive member at bottom portions of the concave portions, a volume resistivity of the matrix is greater than 1&#xd7;10&#x3a9;cm, a volume resistivity of the electro-conductive layer is 1&#xd7;10&#x3a9;cm to 1&#xd7;10&#x3a9;cm, and A2 is 20 times or more of A1.

Electro-conductive member, manufacturing method thereof, process cartridge, and electrophotographic image forming apparatus

Provided is an electrophotographic electro-conductive member including a support having an electro-conductive outer surface, and an electro-conductive layer. The electro-conductive layer has a matrix containing a crosslinked product of a first rubber and domains containing a crosslinked product of a second rubber and an electron conductive agent. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electro-conductive layer while changing a frequency, a slope at specific frequencies is &#x2212;0.8 to &#x2212;0.3 in a double logarithmic plot, and an impedance at specific frequency range is 1.0&#xd7;10&#x3a9; to 1.0&#xd7;10&#x3a9;. When measuring an impedance by applying alternating voltage between the outer surface of the support and a platinum electrode on an outer surface of the electrophotographic electro-conductive member while changing a frequency, an impedance at specific frequency range is 1.0&#xd7;10&#x3a9; to 1.0&#xd7;10&#x3a9;.

Electrophotographic electro-conductive member, process cartridge, and electrophotographic image forming device

A process for producing an electrophotographic electroconductive member having an electroconductive support and an electroconductive layer in the order mentioned. The electroconductive layer has a matrix including a crosslinked product of a first rubber, and a domain including a crosslinked product of a second rubber and an electroconductive particle, the process including the steps of: providing a rubber mixture for forming the domain, including carbon black and the second rubber by kneading the carbon black and the second rubber; providing a rubber mixture for forming the matrix, including the first rubber; kneading the rubber mixture for forming the domain and the rubber mixture for forming the matrix to prepare a rubber composition having a matrix-domain structure; forming a layer of the rubber composition on a surface of the electroconductive support; and curing the layer of the rubber composition on the surface of the electroconductive support to form the electroconductive layer.

Process for producing an electrophotographic electroconductive member

Provided is an electrophotographic electroconductive member including an electroconductive support and an electroconductive layer on the support, an electroconductive member is used, in which an electroconductive layer has a matrix comprising a first rubber, and domains dispersed in the matrix, the domains each comprising a second rubber and an electronic electroconductive agent, and for impedance measured by applying an AC voltage with an amplitude of 1 V to the electroconductive layer while varying frequencies between 1.0&#xd7;10Hz to 1.0&#xd7;10Hz under a specific environment, when a double logarithmic plot with a frequency on an abscissa and an impedance on an ordinate is obtained, a slope on a high frequency side is &#x2212;0.8 or more and &#x2212;0.3 or less, and the impedance a low frequency side is from 1.0&#xd7;10to 1.0&#xd7;10&#x3a9;.

A process cartridge is provided, which is configured to recover, with a developing member, developer remaining on an image bearing member after transfer of a developer image to a transfer receiving member, wherein a charging member has a shaft that is conductive and an elastic layer supported on the shaft and being in contact with the image bearing member; the elastic layer has a matrix containing a first rubber, and a plurality of domains containing a second rubber and an electron-conductive agent and interspersed within the matrix. The electric resistance of the domains is lower than the electric resistance of the matrix. The matrix is exposed on an outer surface of the elastic layer and forms multiple depressed portions, and the domains include a domains exposed at a bottom section of the depressed portion.

Process cartridge and image forming apparatus

An electro-conductive layer of an electrophotographic electro-conductive member has a matrix-domain structure. The matrix contains a first rubber. The domain contains a second rubber and electro-conductive particles. Where &#x3bc; represents an average of ratios of the cross-sectional area of the electro-conductive particles contained in each of the domains to the cross-sectional area of each of the domains appearing on a cross-section of the electro-conductive layer in a thickness direction, and &#x3c3; represents a standard deviation of the ratios, &#x3c3;/&#x3bc; is 0 or more and 0.4 or less, and &#x3bc; is 20% or more and 40% or less. At least eight of samples with a first cubic shape 9 &#x3bc;m on a side, which are sampled at arbitrary nine positions on the electro-conductive layer, satisfy the specified condition.

Electro-conductive member, method for producing same, process cartridge and electrophotographic image forming apparatus

An electroconductive member for electrophotography has an electroconductive support and an electroconductive layer in the order mentioned. The electroconductive layer has a matrix including a crosslinked product of a first rubber, and a domain including a crosslinked product of a second rubber and an electroconductive particle. The impedance of an outer surface of the electroconductive member is 1.0&#xd7;10to 1.0&#xd7;10&#x3a9;. 80% by number or more of domains observed at each of a total of nine 15-&#x3bc;m square observation regions, which are disposed at any three points in a thickness region from the outer surface to a specific depth on each of cross sections in a thickness direction at three points: the center of the electroconductive layer in the longitudinal direction and points at a specific distance from both edges of the electroconductive layer toward the center, satisfy specific requirements.

Electroconductive member, process cartridge, and electrophotographic image forming apparatus

Provided an electrophotographic electro-conductive member that can stably suppress an occurrence of fogging in an electrophotographic image. The member comprises a support having an electro-conductive outer surface, and an electro-conductive layer on the outer surface of the support, the electro-conductive layer having a matrix including a cross-linked product of a first rubber, and domains dispersed in the matrix, the domains each includes a cross-linked product of a second rubber and an electro-conductive particle, at least some of the domains is exposed to the outer surface of the electro-conductive member to constitute protrusions on an outer surface of the member, the outer surface of the electro-conductive member is constituted by the matrix and the domains exposed to the outer surface of the electrophotographic electro-conductive member, the electrophotographic electro-conductive member has an impedance of 1.0&#xd7;10&#x3a9; or more and 1.0&#xd7;10&#x3a9; or less, and some of the domains satisfy two specific requirements.

An electrophotographic developing member includes an electro-conductive support and an electro-conductive layer provided on the support, wherein the electro-conductive layer has a matrix containing a first rubber and a plurality of domains dispersed in the matrix, and the domain contains a second rubber and an electronic conductive agent and when a frequency is log-log-plotted on a horizontal axis and an impedance is log-log-plotted on a vertical axis with respect to an impedance measured by applying an alternating current voltage having an amplitude of 1 V on the electro-conductive layer while changing a frequency between 1.0&#xd7;10Hz to 1.0&#xd7;10Hz under a specific environment, an inclination of an impedance on a high frequency side is &#x2212;0.8 or more and &#x2212;0.3 or less and an impedance on a low frequency side is 1.0&#xd7;10&#x3a9; to 1.0&#xd7;10&#x3a9;.

Developing member, process cartridge and electrophotographic apparatus

Provided an electro-conductive member that can be used as a charging member capable of preventing the emergence of a ghost image. The member comprises an electro-conductive support and an electro-conductive layer, the electro-conductive layer has a matrix including a first cross-linked rubber, and domains, the domains each includes a second cross-linked rubber and an electronically conductive agent, at least some of the domains are exposed to an outer surface of the member to constitute protrusions, the outer surface is constituted by the matrix and the exposed domains, and in a double logarithmic plot with a frequency on the abscissa and an impedance on the ordinate, a slope at a frequency of 1.0&#xd7;10Hz to 1.0&#xd7;10Hz is &#x2212;0.8 to &#x2212;0.3, and an impedance at a frequency of 1.0&#xd7;10Hz to 1.0&#xd7;10Hz is 1.0&#xd7;10to 1.0&#xd7;10&#x3a9;.

Electro-conductive member, process cartridge and image forming apparatus

Provided is a process cartridge having a charging member and an electrophotographic photosensitive member to be charged by being in contact with the charging member, wherein the electrophotographic photosensitive member has a support and a photosensitive layer in this order, and a surface layer of the electrophotographic photosensitive member has a Martens hardness of 230 N/mmor less.

Process cartridge and electrophotographic apparatus

A charging member including an electro-conductive support; and an elastic layer, the elastic layer is a surface layer thereof and is constituted by a mono layer, the elastic layer includes domains and a matrix, an outer surface of the charging member is constituted by a surface of the matrix and surfaces of the domains, and the charging member has concave portions on the outer surface, the domains exist at bottom portions of the respective concave portions and are exposed to the outer surface of the charging member only at the bottom portions of the respective concave portions, the elastic layer has a volume resistivity of 1&#xd7;10&#x3a9;cm or more and 1&#xd7;10&#x3a9;cm or less, and Ais 20 times or more of A, wherein Aand Aare current values obtained by a prescribed method.

Charging member, manufacturing method of charging member, electrophotographic apparatus, and process cartridge

Growing community of inventors

Susono, Japan

Takumi Furukawa