Canon Kabushiki Kaisha

Shoji Amamiya

Akio Maruyama

Tatsuya Ikezue

Noboru Kashimura

Kazushige Nakamura

Hiroki Uematsu

Teigo Sakakibara

Harumi Sakoh

Takahiro Mitsui

Kiyoshi Sakai

Michiyo Sekiya

Masaaki Yamagami

Koichi Nakata

Akira Shimada

Yuichi Hashimoto

Toshihiro Kikuchi

Haruyuki Tsuji

Shuji Ishii

Hideki Ogawa

Takashige Kasuya

Harumi Ishiyama

Hideki Anayama

Kan Tanabe

Kumiko Takizawa

Shin Nagahara

Yoshihisa Saito

Mayumi Oshiro

Koichi Suzuki

Takashi Koyama

Hiroyuki Tanaka

Yukio Nagase

Hideyuki Yano

Katsumi Aoki

Yomishi Toshida

Naoto Fujimura

Tadashi Furuya

Harumi Sakou

Noriko Hirayama

Harumi Sako

Toshiro Kikuchi

An electrophotographic apparatus and a process cartridge include an electrophotographic photosensitive member; a developing unit; and a cleaning unit, wherein depressed portions separated from each other and satisfying conditions below are formed in the surface of the electrophotographic photosensitive member at a density of 10 or more per unit area of 1 cm: a depth of the depressed portions is defined as Rdv[&#x3bc;m], a minor-axis diameter of the depressed portions is defined as Lpc[&#x3bc;m], a major-axis diameter of the depressed portions is defined as Rpc[&#x3bc;m], and an angle formed between a direction of a major-axis of each of the depressed portions and a direction of movement of the surface of the electrophotographic photosensitive member is defined as &#x3b8;[&#xb0;].5[&#xb0;]&#x2266;&#x3b8;[&#xb0;]&#x2266;85[&#xb0;]0.3&#xd7;[&#x3bc;m]&#x2266;[&#x3bc;m]&#x2266;0.5&#xd7;[&#x3bc;m]1.1&#xd7;[&#x3bc;m]&#x2266;[&#x3bc;m]&#x2266;1.5&#xd7;[&#x3bc;m]50/Sin &#x3b8;[&#x3bc;m]&#x2266;[&#x3bc;m]&#x2266;1500[&#x3bc;m]

Electrophotographic apparatus and process cartridge

An electrophotographic photosensitive member is provide which inhibits recovered toner from leaking out of the edge portion at the time of long-term use, and has good durability. Each of at least both edge portions of the surface layer of the electrophotographic photosensitive member has a region in which independent depressed portions are formed at a density of ten or more portions per 100 &#x3bc;m square. An average depth Rdv-A, an average short axis diameter Lpc-A, and an average long axis diameter Rpc-A, of the depressed portions are respectively in specific ranges. When an angle formed between the circumferential direction of the electrophotographic photosensitive member and the long axis of each of the depressed portions is represented by &#x3b8;, the depressed portions are formed so that the angle &#x3b8; satisfies the relationship of 90&#xb0;&#x3c;&#x3b8;&#x3c;180&#xb0; toward the center of the electrophotographic photosensitive member.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

An electrophotographic photosensitive member hard to cause the problem of chatter and wear-out of the cleaning blade and the problem of a rubbing memory, and both a process cartridge and an electrophotographic apparatus having the photosensitive member are provided. The peripheral surface of the photosensitive member has a plurality of dimple-shaped concaves, a 10-point average roughness Rzjis (A) as measured by sweeping along the circumference of the peripheral surface of the photosensitive member is 0.3 to 2.5 &#x3bc;m, a 10-point average roughness Rzjis (B) as measured by sweeping along the generating line of the peripheral surface of the photosensitive member is 0.3 to 2.5 &#x3bc;m, a mean spacing of profile irregularities, RSm (C), as measured by sweeping along the circumference of the peripheral surface of the photosensitive member is 5 to 120 &#x3bc;m, a mean spacing of profile irregularities, RSm (D), as measured by sweeping along the generating line of the photosensitive member is 5 to 120 &#x3bc;m, and the value of a ratio (D/C) of the mean spacing of profile irregularities RSm (D) to the mean spacing of profile irregularities RSm (C) is 0.5 to 1.5.

Electrophotographic Photosensitive member, method for manufacturing electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

An object of the present invention is to improve a phenomenon of the life-shortening of the endurance life due to scratch occurring when recesses of a fixed dimple shape are formed on the surface of the surface layer, in order to inhibit the chattering and folding back of a cleaning blade and the fracture of an edge, which occurs because friction between the surface layer of the surface of an electrophotographic photosensitive member and an abutting member is high; and particularly to improve the above described problems, from initial printing through printing on many sheets, which become particularly remarkable when using an electrophotographic photosensitive member with the use of a curable resin that is improved so as to have a high elastic deformation rate for the surface layer, in order to improve the strength of the surface layer, for the purpose of increasing the durability of an electrophotographic photosensitive member. An electrophotographic photosensitive member for achieving the object, which has a support and an organic photosensitive layer, is characterized in that the electrophotographic photosensitive member has dimple-shaped concavities formed on the surface of the surface layer of the electrophotographic photosensitive member, and further has the recesses with the same pattern as that on the surface of the surface layer, formed on the interface created between the surface layer of the organic photosensitive member and the layer directly under the surface layer (a subsurface layer).

Electrophotographic photosensitive member, method for manufacturing electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

An electrophotographic photosensitive member is disclosed having a cylindrical support and an organic photosensitive layer provided on the cylindrical support. The peripheral surface of the electrophotographic photosensitive member is composed of grooves formed substantially in its peripheral direction and flat portions, and in the grooves, the number of grooves each having a width in the range of from 0.5 &#x3bc;m to 40 &#x3bc;m is from 20 to 1,000 lines per 1,000 &#x3bc;m in width in the generatrix direction of the peripheral surface of the electrophotographic photosensitive member.

Electrophotographic photosensitive member, electrophotographic photosensitive member manufacturing process, process cartridge, and electrophotographic apparatus

An electrophotographic photosensitive member has a support and a photosensitive layer formed thereon. The electrophotographic photosensitive member has a surface layer containing a charge-transporting material and a resin obtained by exposing to radiations a compound having an acryloyloxy group or methacryloyloxy group to cure.

ELECTROPHOTOGRAPHIC PHOTOSENSITVE MEMBER, PROCESS FOR PRODUCING ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER, AND PROCESS CARTRIDGE AND ELECTROPHOTOGRAPHIC APPARATUS WHICH HAVE THE ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

An electrophotographic apparatus includes an electrophotographic photosensitive member; a charger for charging the electrophotographic photosensitive member including a charging member supplied with a voltage and disposed in contact with the photosensitive member so as to form a nip with the photosensitive member to charge the photosensitive member; an exposure device; a developing device; and a transfer device. The photosensitive member includes a surface layer containing a charge-transporting material having an oxidation potential of 0.4-1.0 volt. Charging promoter particles are present at the nip between the photosensitive member and the charging member to injection-charge the photosensitive member. Because of the selection of the charge-transporting material and the presence of the charging promoter particles, the photosensitive member can be effectively injection-charged.

An electrophotographic photosensitive member is comprised of a support and a photosensitive layer formed on the support. The electrophotographic photosensitive member has a surface layer which contains a resin having at least one of the structural units represented by the following formula: ##STR1## wherein the bond represented by a broken line may be present, and when present, m is 4 and when m is 6, n represents an integer of 0 or more, and R.sub.1 and R.sub.2 represent each independently hydrogen, halogen, hydroxy, a substituted or unsubstituted alkyl, a substituted or unsubstituted unsaturated aliphatic hydrocarbon, a substituted or unsubstituted aryl, a substituted or unsubstituted cycloalkyl, a substituted or unsubstituted cyclodienyl, a substituted or unsubstituted alkoxy, a substituted or unsubstituted carbonyl, or a substituted or unsubstituted heterocyclic group.

Electrophotographic photosensitive member, process cartridge, and

A toner image formed on a photosensitive drum is transferred on to an intermediate transfer member, and then, from the intermediate member onto a sheet material. The forming width of charge transporting layer of this photosensitive drum (forming width along the longitudinal direction of the photosensitive drum) is longer by more than 4 mm (2 mm each at the both ends) than the width of the intermediate transfer member. As a result, no image blur occurs in the transferred images even when repeating formation of a transferred image onto the intermediate transfer member and formation of the transferred image onto the sheet material.

Image forming apparatus with extended length charge transporting layer

An electrophotographic apparatus has an electrophotographic photosensitive member having a photosensitive layer on an electroconductive support, a charging means provided in contact with the photosensitive member, and image exposure means, a development means, and an image transfer means. The electrophotographic photosensitive member has a surface layer containing electroconductive particles having particle surface treated with a fluorine-containing compound, and a binder resin.

Electrophotographic apparatus

An electrophotographic photosensitive member is disclosed which comprises a conductive support and a photosensitive layer provided on the conductive support. A surface layer of the electrophotographic photosensitive member contains a polycarbonate resin having a chain fluoroalkyl group having 4 or more carbon atoms. Also, an electrophotographic apparatus and a device unit are disclosed which comprise the electrophotographic photosensitive member.

Electrophotographic photosensitive member having

An electrophotographic apparatus which comprises an electrophotographic photosensitive member, a charging member provided in contact therewith for charging the electrophotographic photosensitive member by being applied with a voltage, a light exposure device, a developing device, and a transfer device, wherein the electrophotographic photosensitive member has a surface layer containing an organic compound having a reduction potential of 0.5 V or lower, and the charging is injection charging.

This invention relates to a charging system for charging a body to be electrified, comprising a body to be electrified, and a charging member which can be applied with voltage to brush the surface of said body to be electrified and charge it. Wherein the surface of the body to be electrified exhibits a contact angle of 90.degree. or more for water.

Charging system and electrophotography apparatus

An electrophotographic apparatus comprises an electrophotographic photosensitive member, and a charging assembly, an exposure assembly, a development assembly, an image-transfer assembly, and a cleaning assembly arranged around the photosensitive member in this order, wherein the photosensitive member has a surface layer containing fluoroplastic particles; and the electrophotographic apparatus further comprises a polishing assembly for polishing the surface of the photosensitive member after the transfer assembly and before the cleaning assembly.

Growing community of inventors

Kawasaki, Japan

Shoji Amamiya