Canon Kabushiki Kaisha

Takahiro Mitsui

Tatsuya Ikezue

Shoji Amamiya

Hideki Ogawa

Koichi Nakata

Hiroki Uematsu

Akira Shimada

Akio Maruyama

Shuji Ishii

Koji Takahashi

Haruki Mori

Kan Tanabe

Kumiko Takizawa

Yasuhiro Kawai

Yoshihisa Saito

Mayumi Oshiro

Tomohisa Itagaki

Tsutomu Nishida

Masaki Nonaka

Ryoichi Tokimitsu

Naoaki Ichihashi

Shubun Kujirai

Provided is an electrophotographic photosensitive member improved both in wear resistance and in image unevenness. The electrophotographic photosensitive member includes a support, and a photosensitive layer and a surface layer on the support, wherein the surface layer is a cured product of a composition containing a compound represented by the formula (A) and a charge-transporting substance having at least one reactive functional group selected from the group consisting of a hydroxy group, a methoxy group, an amino group, a thiol group, and a carboxyl group.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

The present invention provides: an electrophotographic photosensitive member which can achieve both of abrasion resistance and electrical characteristics; a production method of the electrophotographic photosensitive member; and a process cartridge and an electrophotographic apparatus having the electrophotographic photosensitive member. A surface layer of the electrophotographic photosensitive member includes a cured product and a specific amount of an alcohol or carboxylic acid having a specific structure, wherein the cured product is a polymerized product of a hole transporting compound having an acryloyloxy group or a methacryloyloxy group.

Electrophotographic photosensitive member, production method of electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

In an image forming apparatus in which an electrostatic image is formed on an electrophotographic photosensitive member using at least a process of a pseudo halftone formed by dots as a method of representing gradation, the electrophotographic photosensitive member is provided on a surface thereof with a plurality of recessed portions of 0.5 &#x3bc;m more and 5 &#x3bc;m or less in depth and 20 &#x3bc;m or more and 80 &#x3bc;m or less in longest diameter of an opening, when a square region of 500 &#x3bc;m&#xd7;500 &#x3bc;m is arbitrarily extracted on the surface of the electrophotographic photosensitive member, in the square region, a total area of the recessed portions is 10000 &#x3bc;mor more and 90000 &#x3bc;mor less and a total area of a flat portion contained in a portion other than the recessed portion is 80000 &#x3bc;mor more and 240000 &#x3bc;mor less, and an arrangement (A) of the plurality of recessed portions is such an arrangement that an image quality lowering index (f) calculated by specific processing is 14% or less.

Image forming apparatus and electrophotographic photosensitive member

Provided is an electrophotographic photosensitive member in which a surface of the electrophotographic photosensitive member has: a plurality of specific depressed portions; and a plurality of specific line grooves formed at portions other than the specific depressed portions, and in which when a square region 500 &#x3bc;m on a side is arranged at an arbitrary position of the surface of the electrophotographic photosensitive member, an area of the plurality of depressed portions in the square region 500 &#x3bc;m on a side is 95,000 &#x3bc;mor more and 180,000 &#x3bc;mor less.

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.

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

Growing community of inventors

Kawasaki, Japan

Takahiro Mitsui