Canon Kabushiki Kaisha

Kenya Terada

Hiroaki Watanabe

Takumi Furukawa

Yuya Tomomizu

Toshimitsu Nakazawa

Kazuhiro Yamauchi

Yuichi Kikuchi

Masaaki Harada

Keiji Nose

Kenji Takashima

Satoru Nishioka

Masahiro Kurachi

Kazuhiro Gesho

Toshiro Suzuki

Kenichi Yazawa

Masaki Yamada

Tetsuo Hino

Arihiro Yamamoto

Kana Sato

Hiroshi Inoue

Hidekazu Matsuda

Norifumi Muranaka

Masafumi Kyogaku

Takehiko Aoyama

Hisao Kato

Yasuhiro Fushimoto

Mitsuhiro Kunieda

Shota Segawa

Masanori Yokoyama

Toshirou Uchida

Provided is a cleaning member, comprising an elastic member that includes polyurethane, wherein: when tan δ of a test piece sampled from the elastic member is measured in the temperature range of −20° C. to +60° C., the peak temperature of a peak indicating the maximum value of tan δ is at 15.0° C. or below; the maximum value of tan δ is 0.20 to 0.55; tan δ at a temperature of 55° C. is 0.13 or larger; and where the detected quantity of all ions obtained when the test piece is heated at a rate of temperature increase of 10° C./second to 1000° C. using a direct-sampling mass spectrometer is Mand the integrated intensity of a peak in a derived ion thermogram that corresponds to a range of m/z values originating in multifunctional isocyanate with at least three isocyanate groups is M, M/Mis at least 0.001.

Cleaning member and elastic member

An electrophotographic cleaning blade, which includes the following: an elastic member containing polyurethane; and a support member supporting the elastic member, and cleaning a surface of a member to be cleaned in motion, by contact of part of the elastic member against the surface of the member to be cleaned, wherein the elastic member has, at least on the tip side, a plate shape having a main surface facing the member to be cleaned and a leading end surface that forms a tip side edge together with the main surface, and a coefficient of variation of area ratios of white regions in each of sections of a binarized image created from grayscale phase image obtained from the leading end surface, is 20.00 or less, and a value of HM-HMis larger than 0.10 N/mm.

Electrophotography cleaning blade, process cartridge, and electrophotographic image formation device

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

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;.

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

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

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

It is intended to provide a charging member capable of maintaining high charging performance even when used over a long period. The charging member has an electroconductive support and an electroconductive elastic layer as a surface layer, wherein the electroconductive elastic layer has a roughened surface, and the electroconductive elastic layer has an average Martens' hardness Mc of 2 N/mmor larger and 20 N/mmor smaller measured with an indentation strength of 0.04 mN at a core surface defined according to a three dimensional surface texture standard (ISO 25178-2:2012), and has an average viscosity Vc of 70&#xd7;10V or smaller measured in a square of 2 &#x3bc;m long&#xd7;2 &#x3bc;m wide field of view under a scanning probe microscope.

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

The charging member includes: an electroconductive support; and an electroconductive elastic layer serving as a surface layer, wherein the elastic layer contains a binder, and holds electrically insulating hollow particles in such a state that at least a part of each of the hollow particles is exposed at a surface of the elastic layer, wherein the charging member has protrusions derived from the hollow particles in an outer surface of the charging member, and the outer surface of the charging member includes an outer surface of the elastic layer and an outer surface of an exposed portion of each of the hollow particles, and wherein the protrusions each have a depression in an outer surface of each of the protrusions, and an edge of the depression constitutes an apex in each of the protrusions.

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

Provided a charging member comprising an electro-conductive support and an electro-conductive surface layer, the surface layer including on the outer surface thereof, concave portions that are independent of each other, and holding an insulating particle in each of the concave portions, the insulating particle being exposed to the surface of the charging member and forms a convex portion on the surface of the charging member, in an orthogonal projection image of which the concave portions and the insulating particle are projected on a surface of the electro-conductive support, a site in which an outer edge of a projection image derived from the insulating particle and an outer edge of a projection image derived from each of the concave portions are separated, exists, and a part of a wall of each of the concave portions constitutes a part of the surface of the charging member.

Charging member with concave portions containing insulating particles and electrophotographic apparatus

Provided a charging member including an electro-conductive support and a surface layer, the surface layer having in an outer surface thereof, concave portions and holding an elastic particle in each of the concave portions, the elastic particle being exposed at a surface of the charging member to form a convex portion in the surface of the charging member, and a part of a wall of each of the concave portions constituting a part of the surface of the charging member.

Charging member having outer surface with concave portions bearing exposed elastic particles, and electrophotographic apparatus

The present invention provides a charging member having an elastic layer on a surface thereof in which occurrence of compression set is reduced. The charging member includes an electro-conductive support and an elastic layer provided on the support as a surface layer, wherein the elastic layer is a rubber layer made of a crosslinked product of a rubber mixture including acrylonitrile butadiene rubber and polybutadiene, the polybutadiene includes 1,2-syndiotactic polybutadiene, and the elastic layer is formed by irradiating a surface of the rubber layer with electron rays.

Charging member, process cartridge and electrophotographic apparatus

To provide a charging member that can not easily cause faulty cleaning on a photosensitive member while having a flexibility high enough to form a nip between it and the photosensitive member in a sufficient width. The charging member has an electro-conductive support and an elastic layer that is a surface layer, which elastic layer has at its surface a region having been cured by irradiation with electron rays, where this region supports spherical polyethylene particles in such a state that the spherical polyethylene particles are exposed to the surface of the elastic layer, thereby making the surface roughened.

Growing community of inventors

Suntou-gun, Japan

Kenya Terada