Canon Kabushiki Kaisha

Nippon Light Metal Company, Ltd.

Shimizu Construction Co., Ltd.

Yuichi Kikuchi

Kazuhiro Yamauchi

Satoru Nishioka

Norifumi Muranaka

Takumi Furukawa

Masahiro Kurachi

Tetsuo Hino

Satoru Yamada

Masaki Yamada

Masahiro Watanabe

Kenji Takashima

Hiroaki Watanabe

Yuya Tomomizu

Kenya Terada

Toshimitsu Nakazawa

Kana Sato

Kaname Watariguchi

Yasuhiro Fushimoto

Fumiyuki Hiyama

Atsushi Okuda

Tsutomu Nishida

Nobuhiro Nakamura

Yuka Ishiduka

Kenichi Kaku

Hiroyuki Watanabe

Koji Otsuka

Kohei Makisumi

Hideharu Shimozawa

Atsushi Uematsu

Mikio Shimada

Masaki Tsunoda

Takayuki Namiki

Kazuhisa Shida

Shuhei Tokiwa

Takashi Hiramatsu

Takashi Mukai

Seiichi Miyazawa

Fumitoshi Mizutani

Hiroki Masu

Akira Miyazaki

Tomoyuki Hirayama

Masaki Ozawa

Takashi Kawata

Mototeru Goto

Shota Kaneko

Takao Otaki

Nao Higuchi

Kazuhito Seki

Shiroyasu Shimazaki

Masaki Imoto

Tsugio Hida

Masatsugu Hongo

Tomosburo Fujinaga

Yoshiyuki Ohara

Hirotaka Araki

Akihiro Mogi

Tatsunori Akimoto

A process cartridge includes a charging unit, (I) wherein the charging unit includes a conductive member, wherein the conductive member includes a conductive layer disposed on an outer surface of a support, the conductive layer has a matrix-domain structure including a matrix and a plurality of domains, the matrix contains a first rubber, the domains contain a second rubber, and (II) wherein the toner includes agglomerates containing silica fine particles and binding components on surfaces of the toner particles, and wherein a relationship of Dms<Ag is satisfied, where Dms is an arithmetic mean of distances between adjacent domains at the outer surface of the conductive roller, and Ag is an arithmetic mean of Feret diameters of the agglomerates.

Process cartridge and process cartridge set

An electrophotographic conductive member comprising: a conductive layer provided on an outer surface of a support, wherein the conductive layer comprises a plurality of domains dispersed in a matrix, the plurality of domains comprise a crosslinked product of a second rubber and a conductive particle, an outer surface of the electrophotographic conductive member is configured of the matrix and an exposed portion of the domain exposed on the outer surface of the electrophotographic conductive member, an impedance is 1.0×10to 1.0×10Ω of the electrophotographic conductive member, and when specific regions are a first region and a second region, a volume resistivity R1 of a portion being not the conductive particle in the first region and a volume resistivity R2 of a portion being not the conductive particle in the second region satisfy R1>R2.

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

Used is an electro-conductive member for electrophotography including: a support having an electro-conductive outer surface; and an electro-conductive layer on the outer surface of the support, wherein the electro-conductive layer includes: a matrix containing a first crosslinked rubber product and having a volume resistivity greater than 1.0×10Ωcm; and domains dispersed in the matrix, wherein the domain includes a second crosslinked rubber product and an electron conductive agent; and the electro-conductive layer includes a region T in which the volume resistivity of the matrix decreases in a depth direction from the outer surface of the electro-conductive member.

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

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

An electroconductive member for electrophotography including a support having electro-conductivity and an electroconductive layer on the outer surface of the support, the electroconductive layer including a matrix containing a crosslinked product of a first rubber and first electroconductive particles and domains each containing a crosslinked product of a second rubber and second electroconductive particles, wherein at least part of the first electroconductive particles are present as a primary particle in the crosslinked product of the first rubber, wherein, the first electroconductive particles of the matrix observed in a specific observation region have d1 of 200 nm or more, the second electroconductive particles in the domains observed therein have d2 of 50 nm or less, and 80 number % or more of the domains satisfy specific conditions.

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 1.0×10Ω 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

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

A process cartridge which allows any spot and stripe as image defects to be suppressed is provided. A process cartridge, in which an electroconductive layer of a charging member has a matrix including a first rubber, and domains dispersed in the matrix, the domains include a second rubber and an electron electroconductive agent, at least some of the domains are exposed on a surface of the charging member, when a volume resistivity of the matrix is 10times or more a volume resistivity of the domains, a protective layer of an electrophotographic photosensitive member includes a metal oxide particle, and when a number average primary particle size of the metal oxide particle is defined as Sm and an average value of equivalent circle diameters of the domains is defined as Sd, the Sd/Sm satisfies the following expression (1): 0.5&#x3c;Sd/Sm&#x3c;100 . . . expression (1).

Process cartridge and electrophotographic 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 &#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

There is provided a process cartridge detachably attachable to a main body of an electrophotographic apparatus, the process cartridge including an electrophotographic photosensitive member and a charging member, wherein an outer surface of the charging member is composed of at least a matrix and at least a part of domains, a volume resistivity of the matrix is 1.0&#xd7;10times or more of a volume resistivity of the domain, an average value Sd of circle equivalent diameters of the domains observed on the outer surface of the charging member is in a predetermined range, the electrophotographic photosensitive member contains a support, a photosensitive layer, and a protective layer in this order and when a surface roughness of the protective layer is measured, each of a protruding valley portion Rvk, a load length ratio Mr2, and Sd/Rvk is in a predetermined range.

Process cartridge and electrophotographic apparatus using the same

The electro-conductive member has an electro-conductive support, and an electro-conductive layer in this order, the electro-conductive layer including a matrix and domains, the matrix constituted by a first rubber composition containing a cross-linked product of a first rubber, the domains having electro-conductivity, and dispersed in the matrix, each of the domains constituted by a second rubber composition containing a cross-linked product of a second rubber and an electro-conductive particle, the first rubber and the second rubber being diene-based rubbers, the first rubber having at least one monomer unit, the second rubber having at least one monomer unit different from the monomer unit which the first rubber has; a difference of absolute values of SP values between the first rubber and the second rubber is 0.2 (J/cm)to 4.0 (J/cm); and a tan &#x3b4;1/tan &#x3b4;2 is 0.45 to 2.00.

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

The process cartridge includes an electrophotographic photosensitive member having a first support and a photosensitive layer; and a charging member. In the photosensitive member when an electric current is measured which flows when a voltage is applied to a surface while being varied, a gradient aof a low electric field region and a gradient aof a high electric field region satisfy a/a&#x2265;1.50, in a graph. The charging member includes a second support having an electroconductive outer surface, and a second electroconductive layer including a matrix and a plurality of domains being dispersed in the matrix, at least a portion of the domain is exposed to an outer surface which includes at least the matrix and at least a portion of the domain, and a volume resistivity &#x3c1;of the matrix is 1.00&#xd7;10times or higher of a volume resistivity &#x3c1;of the domain.

Growing community of inventors

Susono, Japan

Yuichi Kikuchi