Canon Kabushiki Kaisha

Kunimasa Kawamura

Toshiyuki Ehara

Tetsuya Karaki

Masaki Yamada

Minoru Nakamura

Masahiro Watanabe

Masaya Kawada

Shohei Urushihara

Hironori Ohwaki

Yuji Sakurai

Koji Yamazaki

Ryuji Okamura

Junichiro Hashizume

Takashi Kusaba

Kazuaki Nagaoka

Takashi Koyanagi

Shigenori Ueda

Hironori Owaki

Kazutoshi Ishida

Toru Ishii

Kazuto Hosoi

Arihiro Yamamoto

Ryo Sugiyama

Yasushi Katsuta

Kazuhito Wakabayashi

Makoto Souma

Wataru Moriai

To provide a developing roller having improved toner conveying force in a high-temperature and high-humidity environment. The developing roller has a substrate and an electro-conductive layer on the substrate. The outer surface of the developing roller has an electrical insulating first region and an electro-conductive second region adjacent to the first region and at the same time has at least one groove in the first region.

Developing roller, electrophotographic process cartridge and electrophotographic image forming apparatus

A developing member includes a substrate, an elastic layer, and a surface layer in that order. The surface layer contains a urethane resin and a filler. The urethane resin has: the structure represented by structural formula (1) and at least one of the structures represented by structural formula (2) and structural formula (3), between two adjacent urethane linkages; and the structure represented by structural formula (4) and the structure represented by structural formula (5), between two adjacent urethane linkages. The structural formulas (1) to (5) are as follows: 

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

Provided are a developing unit alleviating fogging occurrence and an electrophotographic image forming apparatus providing images over long periods. The developing unit includes at least a toner of () and a developing roller of (). () When a displacement amount when a load is applied at Y&#xb0; C. and 9.8&#xd7;10N/sec to 2.94&#xd7;10N is X, a displacement amount when the toner is left to stand for 0.1 second is X, a displacement amount when the load is reduced at 9.8&#xd7;10N/sec to 0N is X, and percentage of (X&#x2212;X) to Xis Z(Y), 40&#x2266;Z(25)&#x2266;80 and 10&#x2266;Z(50)&#x2266;55 are satisfied; when a gradient from the origin to the maximum load in the load-displacement curve at 25&#xb0; C. is R(25), 0.49&#xd7;10&#x2266;R(25)&#x2266;1.70&#xd7;10is satisfied; the toner has glass transition temperature TgA (40&#xb0; C.-60&#xb0; C.) and maximum endothermic peak temperature P1 (70&#xb0; C.-110&#xb0; C.), 15&#xb0; C.&#x2266;(P1&#x2212;TgA)&#x2266;70&#xb0; C. is satisfied. () The developing roller includes a surface layer containing a urethane resin having structure (a), and one or both structures (b)-(c). 

Developing unit and electrophotographic image forming apparatus

A high-quality developing member which excels in filming resistance and excels in leak resistance despite high electroconductivity is provided. The developing member includes an electroconductive substrate, an elastic layer formed on the substrate, and a surface layer which covers a surface of the elastic layer. The surface layer includes a first resin which has, between two adjacent urethane linkages, a structure represented by the structural formula (1) and one or both of structures selected from the group consisting of a structure represented by the structural formula (2) and a structure represented by the structural formula (3), a second resin which has a structure represented by the structural formula (4) and one or both of structures selected from the group consisting of a structure represented by the structural formula (5) and a structure represented by the structural formula (6), and an electronically conductive filler.

Developing member, process cartridge, and electrophotographic apparatus

A developing roller which is excellent in image quality and image durability and stably outputs a uniform image, and a process cartridge and an electrophotographic apparatus using the developing roller are provided. The developing roller has a mandrel, an elastic layer and a surface layer covering the elastic layer surface, wherein the surface layer contains a urethane resin having at least one structure of the followings A) and B) between two adjacent urethane linkages: A) a structure represented by the following structural formula (1), and at least one structure selected from the group consisting of structures represented by the following structural formulae (2) and (3), and B) a structure represented by the following structural formula (4), and the surface layer contains polyurethane resin particles of which the elastic part of the indentation work based on ISO 14577-1 is 80% or more, is obtained: 

Developer support member, electrophotographic process cartridge and electrophotographic image forming apparatus

A developing roller includes: a mandrel; an elastic layer provided for an outer periphery of the mandrel, the elastic layer including an addition-curing silicone rubber; and a surface layer provided for an outer periphery of the elastic layer, in which: the elastic layer includes a compound represented by the following formula (1); when the content of such a compound that n in the formula (1) represents an integer of 3 to 12 in the elastic layer is represented by P1, and the content of such a compound that n in the formula (1) represents an integer of 13 to 20 in the elastic layer is represented by P2, P1+P2 is 5,000 ppm by mass to 12,000 ppm by mass; and P1 is 1,500 ppm by mass to 6,000 ppm by mass (In the formula (1), n represents an integer of 3 to 20): 

Developing member including elastic member containing cured product of addition-curing silicone rubber mixture, processing cartridge including the developing member, and electrophotographic apparatus including the developing member

A regenerated elastic rollers manufacturing process is provided. The process includes the step of removing an agglutinated stain of toner adhered to the surface of an elastic roller including a mandrel and an elastic layer. The step further includes the steps of: (1) pressing a pressing roller against the surface of the elastic roller so as to crack the agglutinated stain on the surface of the elastic roller; and (2) removing the agglutinated stain cracked in the step (1) from the surface of the elastic roller by means of an adhesive roller.

Regenerated elastic roller manufacturing process, regenerated elastic roller, electropohotographic process cartridge, and electropohotographic image forming apparatus

Provided is a developing member capable of suppressing a variation in resistance even when exposed to a high-temperature, high-humidity environment for a long time period. The developing member comprises: a mandrel; an electro-conductive elastic layer provided on a periphery of the mandrel; and a surface layer provided on a surface of the elastic layer, wherein: the elastic layer contains a dimethyl silicone rubber and carbon black; and an amount &#x3b1; of a hydrogen atom bound to a silicon atom of the dimethyl silicone rubber, and an amount &#x3b2; of a hydrogen atom of methyl groups bound to a silicon atom of the dimethyl silicone rubber, satisfy a relationship of 2.5&#xd7;10&#x2266;&#x3b1;/&#x3b2;&#x2266;1.0&#xd7;10.

Developing member, process cartridge, and electrophotographic image forming apparatus

A developing roller including a mandrel, an elastic layer provided on the mandrel and containing a cured material of an addition curable-type dimethyl silicone rubber, and a surface layer containing a urethane resin that covers the circumferential surface of the elastic layer. The urethane resin has a structure represented by the following formula (1), and one or both structures selected from a structure represented by the following formula (2) and a structure represented by the following formula (3) between two adjacent urethane linkages. 

Developing roller, process cartridge, and electrophotographic apparatus

There is provided a process for producing a regenerated elastic roller which can be again used for the formation of high-quality electrophotographic images by sufficiently relaxing a compression set of the elastic roller having the compression set caused in an elastic layer in usage. The process for producing a regenerated elastic roller includes a step of heating an elastic roller having a conductive mandrel and an elastic layer and having a compression set caused in the elastic layer, in a cylindrical mold to thermally expand the elastic layer and to cause a surface of the elastic roller to contact an inner wall of the cylindrical mold.

Process for producing regenerated elastic roller

An object of the present invention is to provide a production process of a roller for an electrophotography, having a surface layer the electric resistance of which has been controlled by corona discharge treatment while keeping any pinholes from coming about on the surface. A production process of a roller for an electrophotography, said roller comprising a conductive mandrel and a conductive surface layer comprising a resin and carbon black dispersed in the resin, the process having the following steps (1) to (3):

Process for producing roller for electrophotography

Regenerated elastic roller manufacturing process, regenerated elastic roller, electrophotographic process cartridge, and electrophotographic image forming apparatus

To provide an electrophotographic developing member which can both be kept from the sticking of a developer and be kept from being deformed by its contacting members, and can form stable images over a long period of time. An electrophotographic developing member characterized in that its surface layer satisfies the following expressions (1) to (3) where the average crosslinking density in each region of up to 100 nm in depth, from 100 nm to 200 nm in depth and from 200 nm to 300 nm in depth from the surface of the surface layer is represented by C, Cand C(mol/cm), respectively:C3&#x3c;C2&#x3c;C1;&#x2003;&#x2003;(1)3&#xd7;1.3&#x2266;1&#x2266;3&#xd7;5.0; and&#x2003;&#x2003;(2)2.0&#xd7;103&#x2266;7.0&#xd7;10.&#x2003;&#x2003;(3)

Electrophotographic developing member, process for its production, electrophotographic process cartridge and electrophotographic image forming apparatus

A light-receiving member comprising a conductive substrate, and formed superposingly thereon a photosensitive layer and a surface protective layer in order. The light-receiving member has a surface roughness Ra of from 15 nm to 100 nm. Also disclosed is an image-forming apparatus having such a light-receiving member, and an image-forming method of rendering visible an electrostatic pattern formed on the light-receiving member. The light-receiving member promises stable formation of images over a long period of time.

Light-receiving member, image-forming apparatus, and image-forming method

A process for producing an electrophotographic photosensitive member comprising the steps of depositing a non-single crystal material composed basically of silicon atoms, on a cylindrical substrate in a deposition chamber, thereafter once taking the substrate with film out of the deposition chamber, then returning it to the deposition chamber, and thereafter again depositing thereon a non-single-crystal material composed basically of carbon atoms. In another embodiment, the process comprises the steps of depositing on a cylindrical substrate a photoconductive layer formed of a non-single crystal material, subjecting to surface processing the deposited film having protrusions present at its surface, and depositing on the processed surface a surface protective layer formed of a non-single-crystal material. Also disclosed is the electrophotographic photosensitive member thus obtained, and an electrophotographic apparatus having that member.

Growing community of inventors

Mishima, Japan

Kunimasa Kawamura