Canon Kabushiki Kaisha

Hiroki Uematsu

Harunobu Ogaki

Akio Maruyama

Atsushi Ochi

Toshihiro Kikuchi

Akira Shimada

Atsushi Okuda

Masataka Kawahara

Shoji Amamiya

Takayuki Sumida

Akio Koganei

Kyoichi Teramoto

Koji Takahashi

Michiyo Sekiya

Kimihiro Yoshimura

Yohei Miyauchi

Keiko Yamagishi

Yasuhiro Kawai

Shuji Ishii

Takahiro Mitsui

Koichi Nakata

Tatsuya Ikezue

Takeshi Murakami

Tsutomu Nishida

Akihiro Maruyama

Shio Murai

Hideki Ogawa

Hiroyuki Tanaka

Tomohisa Itagaki

Kazunori Noguchi

Takashi Anezaki

Hideki Anayama

Hirotoshi Uesugi

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 are a method of producing an electrophotographic photosensitive member, particularly, a method of producing an electrophotographic photosensitive member and an organic device by which, in a method of forming a charge transporting layer, the stability of an application liquid for the layer after long-term storage is improved while the usage of an organic solvent in the application liquid is curtailed, and the layer having high uniformity is formed. The method is a method of producing an electrophotographic photosensitive member which includes a support and a charge transporting layer formed thereon, the method including: preparing a solution including: a first liquid whose solubility in water under 25&#xb0; C. and 1 atmosphere is 1.0 mass % or less; a second liquid whose solubility in water under 25&#xb0; C. and 1 atmosphere is 5.0 mass % or more; a charge transporting substance; and a binder resin; preparing an emulsion by dispersing the solution in water; forming a coat for the layer on the support by using the emulsion; and forming the layer by heating of the coat.

Method of producing electrophotographic photosensitive member, method of producing organic device, and emulsion for charge transporting layer

The invention has a process of preparing a dispersion liquid by dispersing particles containing a charge transporting substance and a binder resin in liquid medium containing a specific liquid to prepare a dispersion liquid and a process of forming a coat of the dispersion liquid, and heating and drying the coat to dissolve the particles containing the charge transporting substance and the binder resin with liquid medium to form a charge transporting layer.

Method of producing electrophotographic photosensitive member

A method of producing an electrophotographic photosensitive member includes: preparing a solution including a charge transporting substance, and at least one compound selected from the group consisting of a fluorine-atom-containing polyacrylate, a fluorine-atom-containing polymethacrylate, a polycarbonate having a siloxane bond, a polyester having a siloxane bond, a polystyrene having a siloxane bond, a silicone oil, a polyolefin, an aliphatic acid, an aliphatic acid amide and an aliphatic acid ester; preparing an emulsion by using the solution and water; forming a coat of the emulsion on a support; and heating the coat to form a charge transporting layer.

Method of producing electrophotographic photosensitive member, and emulsion for a charge transporting layer

In a process for producing an electrophotographic photosensitive member, in particular, a process of forming a charge transporting layer, a production process is provided by which the stability of a charge transporting layer coating fluid even after its storage for a long time is improved so as to form a coat for a charge transporting layer having a high uniformity. In a process for producing an electrophotographic photosensitive member having a charge transporting layer on a support, a production process is used in which a coat of (i) a liquid dispersion comprised of particles containing a charge transporting material, particles containing a binder resin, and an aqueous dispersion medium, or (ii) a liquid dispersion comprised of particles containing both a charge transporting material and a binder resin, and an aqueous dispersion medium, is formed on the support and then the coat is heated at a temperature not less than the melting point of the charge transporting material to form the charge transporting layer.

Process for producing electrophotographic photosensitive member

The present invention provides a method of producing an electrophotographic photosensitive member in which the amount of an organic solvent to be used for a coating solution for a charge transporting layer is reduced, and the stability of the coating solution for a charge transporting layer after preservation for a long time is improved, enabling formation of a charge transporting layer having high uniformity. The method includes: preparing a solution containing a charge transporting substance, a resin having a carbonyl group, and at least one compound selected from the group consisting of a compound represented by the formula (A), a compound represented by the formula (B), a compound represented by the formula (C), a compound represented by the formula (D), and a compound represented by the formula (E); dispersing the solution in water to prepare an emulsion; forming a coat by using the emulsion; and heating the coat to form a charge transporting layer.

A method for producing an electrophotographic photosensitive member has a charge transporting layer, including preparing a first solution containing a specified first liquid, a charge transporting substance and a binder resin, preparing a second solution containing a specified second liquid and water, preparing an emulsion from the first and second solutions, forming the emulsion coating, and heating the coat to form the charge transporting layer, and a method for producing an organic device has a charge transporting layer, including preparing a first solution containing a specified first liquid and a charge transporting substance, preparing a second solution containing a specified second liquid and water, preparing an emulsion from the first and second solutions, forming the emulsion coating, and heating the coat to form the charge transporting layer are used.

Methods for producing electrophotographic photosensitive member and organic device each having charge transporting layer

In the case where an uneven structure is formed on the surface of cylindrical electrophotographic photosensitive members, for the purpose of reducing the variation of the uneven structure between the individual cylindrical electrophotographic photosensitive members even when a large number of cylindrical electrophotographic photosensitive members are continuously processed, an insert is inserted into the interior of a cylindrical electrophotographic photosensitive member including a cylindrical substrate and a surface layer, the surface uneven structure of a molding member is transferred to and formed on the surface of the surface layer of the photosensitive member. The insert includes an abutting part having an outer peripheral surface capable of abutting on the inner peripheral surface of the substrate, a connecting part positioned inside of the abutting part in the radical direction and a shaft part positioned inside of the connecting part in the radical direction.

Process for forming uneven structure on surface of surface layer of cylindrical electrophotographic photosensitive member, and process for producing cylindrical electrophotographic photosensitive member having uneven structure formed on surface of surface layer of same

An electrophotographic photosensitive member having excellent cleaning performance, a process cartridge, and an electrophotographic apparatus. The peripheral surface of the member has flat portions having a width e (&#x3bc;m) satisfying 0.1&#x2266;e&#x2266;25 and a plurality of groove portions having a width w (&#x3bc;m) satisfying 0.1&#x2266;w&#x2266;25 and a depth d (&#x3bc;m) satisfying 0.1&#x2266;d&#x2266;3.0, the flat and groove portions at an angle &#x3b8; (&#xb0;) satisfying 80&#x2266;&#x3b8;&#x2266;100 with respect to the axial direction of the member. The sum e(&#x3bc;m) of the widths e of the flat portions per each width of&#x3bc;m in the axial direction of the peripheral surface satisfying 5&#x2266;e&#x2266;75, and e/esatisfying e/e&#x2266;0.46, where e(&#x3bc;m) is the average value of the widths e of the flat portions, and eis the standard deviation thereof.

Electrophotographic photosensitive member, process cartridge, and electrophotographic apparatus

An electrophotographic apparatus is provided including an electrophotographic photosensitive member which includes a surface protective layer; and an exposure device which irradiates a surface of the electrophotographic photosensitive member with an exposure beam so as to form an electrostatic latent image on the surface of the electrophotographic photosensitive member, wherein the surface protective layer includes a material having no structure to provide charge transporting performance and has a plurality of through holes penetrating from the side of the front surface of the surface protective layer to the side of the charge transport layer, and the thickness of the surface protective layer is from 0.1 &#x3bc;m or more to 1.5 &#x3bc;m or less, and wherein when the surface of the electrophotographic photosensitive member is irradiated with the exposure beam, two or more of the through holes are included in an exposure beam spot.

Electrophotographic apparatus

A method for producing a solid body having depressed portions on its surface is provided. The method includes: using a solution which includes a solvent A, a solvent B, a solvent C, and a polymer compound, where the solvent B is a hydrophobic solvent, the solvent A is a hydrophilic solvent having a boiling point not lower than the boiling point of the solvent B, and the solvent C is a non-hydrophobic solvent having a boiling point lower than the boiling point of the solvent B, and the contents of the solvent A, solvent B, and solvent C satisfy specific conditions; and solidifying the solution while forming depressed portions on the surface of the solution by condensation during the process of evaporating the solvents included in the solution.

Method of producing solid body having depressed portions on its surface and method of producing electrophotographic photosensitive member

A charge transport layer serving as a surface layer of an electrophotographic photosensitive member contains a polyester resin having a repeating structural unit represented by the following formula (1) and a repeating structural unit represented by the following formula (2), as a binder resin; the content of a siloxane moiety of the polyester resin is not less than 5% by mass and not more than 30% by mass relative to the total mass of the polyester resin; and the content of the polyester resin in the charge transport layer is not less than 60% by mass relative to the total mass of the whole binder resin in the charge transport layer. 

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

A charge transport layer serving as a surface layer of an electrophotographic photosensitive member contains a charge transporting material, polyester resin A containing a siloxane moiety and at least one of polyester resin C and polycarbonate resin D. The content of a siloxane moiety in polyester resin A is not less than 10% by mass and not more than 40% by mass relative to the total mass of polyester resin A. The charge transport layer has a matrix-domain structure having a matrix formed of the charge transporting material and at least one of polyester resin C and polycarbonate resin D and a domain formed of polyester resin A in the matrix.

Electrophotographic photosensitive member having siloxane-polyester, process cartridge and electrophotographic apparatus

An image forming method is disclosed having a charging step, an exposure step, a developing step and a transfer step. This method uses a toner which includes toner particles containing a binder resin and a colorant, and inorganic fine powder, and uses a photosensitive member which has on its surface depressed portions which are independent of one another. The depressed portions have openings having an average minor-axis diameter Lpc satisfying the relationship of Dg&#x3c;Lpc&#x3c;Dt (Dt represents the weight-average particle diameter of the toner, and Dg represents the maximum number-average particle diameter among number-average particle diameter(s) of one or two or more types of inorganic fine powder constituting the inorganic fine powder, and the toner has an average circularity of from 0.925 to 0.995.

Image forming method, and electrophotographic apparatus making use of the image forming method

An electrophotographic photosensitive member is disclosed which is excellent in cleaning performance, has improved durability, and suppresses image defects in various environments. The electrophotographic photosensitive member has a support and a photosensitive layer provided on the support. Depressed portions independent of one another are formed on the surface of the electrophotographic photosensitive member so that the number of the depressed portions per 100 &#x3bc;m square is 76 or more and 1,000 or less. The openings of the depressed portions have an average major axis diameter of more than 3.0 &#x3bc;m and 14.0 &#x3bc;m or less.

Electrophotographic photosensitive member with depressed portions, process cartridge holding the electrophotographic photosensitive member and electrophotographic apparatus with the electrophotographic photosensitive member

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Mishima, Japan

Hiroki Uematsu