Patents by Inventor Hiroshi Nagame

Hiroshi Nagame has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7482104
    Abstract: An image forming method, includes: forming a latent electrostatic image on a latent electrostatic image carrier; developing the latent electrostatic image with a toner to thereby form a visible image; transferring the visible image to a recording medium; and fixing the image transferred to the recording medium. The latent electrostatic image carrier includes: a support, a photoconductive layer on the support, and a surface protective layer on the support. The surface protective layer includes a reactant made by cross-linking the following: an electric charge transporting material which comprises a reactive functional group, a cross-linking resin, and a fluorine surfactant. The toner comprises an inorganic fine particle which defines an effective inorganic fine particle amount in a range of 0.8% by mass to 3.
    Type: Grant
    Filed: April 16, 2008
    Date of Patent: January 27, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Maiko Kondo, Hidetoshi Kami, Naohiro Toda, Ryoichi Kitajima, Hiroshi Nagame, Narihito Kojima, Yoshiaki Kawasaki
  • Publication number: 20080193865
    Abstract: An image forming method, includes: forming a latent electrostatic image on a latent electrostatic image carrier; developing the latent electrostatic image with a toner to thereby form a visible image; transferring the visible image to a recording medium; and fixing the image transferred to the recording medium. The latent electrostatic image carrier includes: a support, a photoconductive layer on the support, and a surface protective layer on the support. The surface protective layer includes a reactant made by cross-linking the following: an electric charge transporting material which comprises a reactive functional group, a cross-linking resin, and a fluorine surfactant. The toner comprises an inorganic fine particle which defines an effective inorganic fine particle amount in a range of 0.8% by mass to 3.
    Type: Application
    Filed: April 16, 2008
    Publication date: August 14, 2008
    Inventors: Maiko KONDO, Hidetoshi Kami, Naohiro Toda, Ryoichi Kitajima, Hiroshi Nagame, Narihito Kojima, Yoshiaki Kawasaki
  • Patent number: 7386256
    Abstract: An image forming method, includes: forming a latent electrostatic image on a latent electrostatic image carrier; developing the latent electrostatic image with a toner to thereby form a visible image; transferring the visible image to a recording medium; and fixing the image transferred to the recording medium. The latent electrostatic image carrier includes: a support, a photoconductive layer on the support, and a surface protective layer on the support. The surface protective layer includes a reactant made by cross-linking the following: an electric charge transporting material which comprises a reactive functional group, a cross-linking resin, and a fluorine surfactant. The toner comprises an inorganic fine particle which defines an effective inorganic fine particle amount in a range of 0.8% by mass to 3.
    Type: Grant
    Filed: December 9, 2004
    Date of Patent: June 10, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Maiko Kondo, Hidetoshi Kami, Naohiro Toda, Ryoichi Kitajima, Hiroshi Nagame, Narihito Kojima, Yoshiaki Kawasaki
  • Patent number: 7341814
    Abstract: An electrophotographic photoconductor includes an electroconductive substrate, a photoconductive layer arranged over the electroconductive layer with or without the interposition of an undercoat layer, and a surface top layer containing a crosslinkable resin arranged over the photoconductive layer, the photoconductive layer includes a charge generation layer containing a charge generating material, and a charge transport layer containing a charge transporting material, in which the surface top layer is substantially free from hydroxyl groups and residual uncured portions.
    Type: Grant
    Filed: January 7, 2005
    Date of Patent: March 11, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidetoshi Kami, Naohiro Toda, Yoshiaki Kawasaki, Maiko Kondo, Ryoichi Kitajima, Narihito Kojima, Hiroshi Nagame
  • Patent number: 7315722
    Abstract: An image forming apparatus, including an electrophotographic photoreceptor including: an electroconductive substrate, a photosensitive layer overlying the electroconductive substrate, and a protective layer overlying the photosensitive layer and serving as an outermost layer, wherein the protective layer has an average abraded thickness not greater than 1 ?m after the electrophotographic image forming apparatus produces 100,000 images; a charger charging the electrophotographic photoreceptor; an irradiator irradiating the electrophotographic photoreceptor to form an electrostatic latent image thereon; an image developer developing the electrostatic latent image with a toner to form a toner image on the electrophotographic photoreceptor; a transferer transferring the toner image onto a transfer sheet; and a cleaner cleaning a surface of the electrophotographic photoreceptor, wherein the cleaner comprises a cleaning brush impregnated with a resin.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: January 1, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryoichi Kitajima, Hidetoshi Kami, Yoshiaki Kwasaki, Naohiro Toda, Maiko Kondoh, Hiroshi Nagame
  • Patent number: 7177570
    Abstract: An image forming apparatus includes a photoconductor having a surface with a frictional resistance ranging from 45 gram-force to 200 gram-force, a 10-point average roughness RzJIS ranging from 0.1 mm to 1.5 mm or a maximum height Rz of 2.5 mm. Image formation is performed by the image forming apparatus to allow irregular-shaped toner or spherical toner to be cleaned off efficiently and any background stain on a copied sheet to be prevented. A lubricant is applied to the photoconductor so as to form a nonuniform film thereon, which prevents the frictional resistance from abnormally lowering, thus suppressing image degradation.
    Type: Grant
    Filed: February 27, 2004
    Date of Patent: February 13, 2007
    Assignee: Ricoh Company, Limited
    Inventors: Hiroshi Nagame, Hidetoshi Kami, Katsuichi Ohta
  • Patent number: 7153621
    Abstract: An electrophotographic photoreceptor including a photosensitive layer on an electroconductive substrate, wherein nitrate ion is present on the surface of the photosensitive layer in an amount of from 50 to 300 ?g per 1 m2 of the surface of the photosensitive layer when the nitrate ion is determined by an ion chromatographic method. Preferably a material having a fluorine atom and a carbon atom or a fatty acid metal salt such as zinc stearate is further present on the surface of the photosensitive layer such that the F/C ratio is from 0.05 to 0.5 or the Zn/C ratio is from 0.001 to 0.1. An image forming apparatus using the photoreceptor is also provided.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: December 26, 2006
    Assignee: Ricoh Company Limited
    Inventors: Narihito Kojima, Ryuta Takeichi, Akiyo Namiki, Hiroshi Nagame, Yohta Sakon
  • Publication number: 20050238977
    Abstract: An electrophotographic photoreceptor including a photosensitive layer on an electroconductive substrate, wherein nitrate ion is present on the surface of the photosensitive layer in an amount of from 50 to 300 ?g per 1 m2 of the surface of the photosensitive layer when the nitrate ion is determined by an ion chromatographic method. Preferably a material having a fluorine atom and a carbon atom or a fatty acid metal salt such as zinc stearate is further present on the surface of the photosensitive layer such that the F/C ratio is from 0.05 to 0.5 or the Zn/C ratio is from 0.001 to 0.1. An image forming apparatus using the photoreceptor is also provided.
    Type: Application
    Filed: June 24, 2005
    Publication date: October 27, 2005
    Inventors: Narihito Kojima, Ryuta Takeichi, Akiyo Namiki, Hiroshi Nagame, Yohta Sakon
  • Publication number: 20050181291
    Abstract: An electrophotographic photoconductor includes an electroconductive substrate, a photoconductive layer arranged over the electroconductive layer with or without the interposition of an undercoat layer, and a surface top layer containing a crosslinkable resin arranged over the photoconductive layer, the photoconductive layer includes a charge generation layer containing a charge generating material, and a charge transport layer containing a charge transporting material, in which the surface top layer is substantially free from hydroxyl groups and residual uncured portions.
    Type: Application
    Filed: January 7, 2005
    Publication date: August 18, 2005
    Inventors: Hidetoshi Kami, Naohiro Toda, Yoshiaki Kawasaki, Maiko Kondo, Ryoichi Kitajima, Narihito Kojima, Hiroshi Nagame
  • Publication number: 20050158644
    Abstract: An image forming method, includes: forming a latent electrostatic image on a latent electrostatic image carrier; developing the latent electrostatic image with a toner to thereby form a visible image; transferring the visible image to a recording medium; and fixing the image transferred to the recording medium. The latent electrostatic image carrier includes: a support, a photoconductive layer on the support, and a surface protective layer on the support. The surface protective layer includes a reactant made by cross-linking the following: an electric charge transporting material which comprises a reactive functional group, a cross-linking resin, and a fluorine surfactant. The toner comprises an inorganic fine particle which defines an effective inorganic fine particle amount in a range of 0.8% by mass to 3.
    Type: Application
    Filed: December 9, 2004
    Publication date: July 21, 2005
    Inventors: Maiko Kondo, Hidetoshi Kami, Naohiro Toda, Ryoichi Kitajima, Hiroshi Nagame, Narihito Kojima, Yoshiaki Kawasaki
  • Publication number: 20050141919
    Abstract: An image forming apparatus, including an electrophotographic photoreceptor including: an electroconductive substrate, a photosensitive layer overlying the electroconductive substrate, and a protective layer overlying the photosensitive layer and serving as an outermost layer, wherein the protective layer has an average abraded thickness not greater than 1 ?m after the electrophotographic image forming apparatus produces 100,000 images; a charger charging the electrophotographic photoreceptor; an irradiator irradiating the electrophotographic photoreceptor to form an electrostatic latent image thereon; an image developer developing the electrostatic latent image with a toner to form a toner image on the electrophotographic photoreceptor; a transferer transferring the toner image onto a transfer sheet; and a cleaner cleaning a surface of the electrophotographic photoreceptor, wherein the cleaner comprises a cleaning brush impregnated with a resin.
    Type: Application
    Filed: December 21, 2004
    Publication date: June 30, 2005
    Inventors: Ryoichi Kitajima, Hidetoshi Kami, Yoshiaki Kwasaki, Naohiro Toda, Maiko Kondoh, Hiroshi Nagame
  • Patent number: 6879799
    Abstract: An image-forming apparatus which includes an image developer configured to develop a latent electrostatic image and to have a developer, a developer bearing member which has a magnet therein, has the developer on a surface thereof, and rotates with carrying the developer, and a developer limiting member which faces the developer bearing member, and controls an amount of the developer, and a latent electrostatic image support configured to contain a filler in its outermost layer. In the image-forming apparatus, the developer is a double-component developer which contains a magnetic carrier and a toner, the magnetic carrier has a coating layer which is formed of a binder resin having particles retained on a surface of the magnetic carrier, and a ratio of a particle diameter D1 of the particles to a film thickness h1 of the binder resin satisfies a relation of: 1<D1/h1<10.
    Type: Grant
    Filed: March 11, 2003
    Date of Patent: April 12, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinji Nohsho, Hiroshi Nagame, Hidetoshi Kami
  • Patent number: 6844124
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate and including a resin; and a surface layer including a filler and a binder resin, wherein the surface layer and the photosensitive layer have a continuous structure, and wherein the surface layer satisfies the following relationship: ??D/5, wherein D represents an average of maximum thicknesses of the surface layer in units of micrometers in 20 segments of 5 ?m wide when a portion of a cross section of the photoreceptor of 100 ?m wide is divided into the 20 segments, and ? represents a standard deviation of the 20 maximum thicknesses.
    Type: Grant
    Filed: August 12, 2003
    Date of Patent: January 18, 2005
    Assignee: Ricoh Company Limited
    Inventors: Hiroshi Ikuno, Hidetoshi Kami, Ryohichi Kitajima, Narihito Kojima, Akihiko Matsuyama, Hiroshi Nagame, Katsuichi Ohta, Tetsuro Suzuki, Nozomu Tamoto, Hiroshi Tamura, Yohta Sakon, Eiji Kurimoto, Tatsuya Niimi, Yuka Miyamoto
  • Publication number: 20040234294
    Abstract: An image forming apparatus includes a photoconductor having a surface with a frictional resistance ranging from 45 gram-force to 200 gram-force, a 10-point average roughness RzJIS ranging from 0.1 &mgr;m to 1.5 &mgr;m s or a maximum height Rz of 2.5 &mgr;m. Image formation is performed by the image forming apparatus to allow irregular-shaped toner or spherical toner to be cleaned off efficiently and any background stain on a copied sheet to be prevented. A lubricant is applied to the photoconductor so as to form a nonuniform film thereon, which prevents the frictional resistance from abnormally lowering, thus suppressing image degradation.
    Type: Application
    Filed: February 27, 2004
    Publication date: November 25, 2004
    Inventors: Hiroshi Nagame, Hidetoshi Kami, Katsuichi Ohta
  • Patent number: 6706459
    Abstract: An electrophotographic drum-shaped photoconductor has an electroconductive support and a photoconductive layer formed thereon, with a lubricating material being applied to the surface thereof in the shape of a plurality of bands spaced therebetween, constituting band-shaped lubricating material applied areas, extending along a circumference of the drum-shaped photoconductor in the direction perpendicular or substantially perpendicular to an axis of rotation of the drum-shaped photoconductor. An electrophotographic image formation method and an image forming apparatus employing the above-mentioned drum-shaped photoconductor are also disclosed.
    Type: Grant
    Filed: March 3, 2003
    Date of Patent: March 16, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Narihito Kojima, Ryuta Takeichi, Akiyo Nakajima, Hiroshi Nagame, Yohta Sakon
  • Publication number: 20040048178
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate and including a resin; and a surface layer including a filler and a binder resin, wherein the surface layer and the photosensitive layer have a continuous structure, and wherein the surface layer satisfies the following relationship: &sgr;≦D/5, wherein D represents an average of maximum thicknesses of the surface layer in units of micrometers in 20 segments of 5 &mgr;m wide when a portion of a cross section of the photoreceptor of 100 &mgr;m wide is divided into the 20 segments, and &sgr; represents a standard deviation of the 20 maximum thicknesses.
    Type: Application
    Filed: August 12, 2003
    Publication date: March 11, 2004
    Inventors: Hiroshi Ikuno, Hidetoshi Kami, Ryohichi Kitajima, Narihito Kojima, Akihiko Matsuyama, Hiroshi Nagame, Katsuichi Ohta, Tetsuro Suzuki, Nozomu Tamoto, Hiroshi Tamura, Yohta Sakon, Eiji Kurimoto, Tatsuya Niimi, Yuka Miyamoto
  • Patent number: 6686114
    Abstract: An image forming apparatus including a photoreceptor configured to bear an electrostatic latent image while rotating in a direction, wherein the photoreceptor includes an electroconductive substrate, a photosensitive layer located overlying the substrate, and a protective layer located overlying the photosensitive layer and including a filler; a latent image former configured to form the electrostatic latent image on the photoreceptor; an image developer configured to develop the electrostatic latent image with a developer including a toner; an image transfer device configured to transfer the toner image onto a receiving material; a cleaner configured to remove the toner remaining on the surface of the photoreceptor while contacting the surface of the photoreceptor; and a surface condition controller configured to control a surface condition of the photoreceptor.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: February 3, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Yohta Sakon, Hiroshi Nagame, Narihito Kojima, Hiroshi Ikuno
  • Publication number: 20030219279
    Abstract: An image-forming apparatus which includes an image developer configured to develop a latent electrostatic image and to have a developer, a developer bearing member which has a magnet therein, has the developer on a surface thereof, and rotates with carrying the developer, and a developer limiting member which faces the developer bearing member, and controls an amount of the developer, and a latent electrostatic image support configured to contain a filler in its outermost layer. In the image-forming apparatus, the developer is a double-component developer which contains a magnetic carrier and a toner, the magnetic carrier has a coating layer which is formed of a binder resin having particles retained on a surface of the magnetic carrier, and a ratio of a particle diameter D1 of the particles to a film thickness h1 of the binder resin satisfies a relation of: 1<D1/h1<10.
    Type: Application
    Filed: March 11, 2003
    Publication date: November 27, 2003
    Inventors: Shinji Nohsho, Hiroshi Nagame, Hidetoshi Kami
  • Patent number: 6641964
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate; a photosensitive layer located overlying the electroconductive substrate and including a resin; and a surface layer including a filler and a binder resin, wherein the surface layer and the photosensitive layer have a continuous structure, and wherein the surface layer satisfies the following relationship: &sgr;≦D/5, wherein D represents an average of maximum thicknesses of the surface layer in units of micrometers in 20 segments of 5 &mgr;m wide when a portion of a cross section of the photoreceptor of 100 &mgr;m wide is divided into the 20 segments, and &sgr; represents a standard deviation of the 20 maximum thicknesses.
    Type: Grant
    Filed: November 2, 2001
    Date of Patent: November 4, 2003
    Assignee: Ricoh Company Limited
    Inventors: Hiroshi Ikuno, Hidetoshi Kami, Ryohichi Kitajima, Narihito Kojima, Akihiko Matsuyama, Hiroshi Nagame, Katsuichi Ohta, Tetsuro Suzuki, Nozomu Tamoto, Hiroshi Tamura, Yohta Sakon, Eiji Kurimoto, Tatsuya Niimi, Yuka Miyamoto
  • Publication number: 20030165757
    Abstract: An electrophotographic drum-shaped photoconductor has an electroconductive support and a photoconductive layer formed thereon, with a lubricating material being applied to the surface thereof in the shape of a plurality of bands spaced therebetween, constituting band-shaped lubricating material applied areas, extending along a circumference of the drum-shaped photoconductor in the direction perpendicular or substantially perpendicular to an axis of rotation of the drum-shaped photoconductor. An electrophotographic image formation method and an image forming apparatus employing the above-mentioned drum-shaped photoconductor are also disclosed.
    Type: Application
    Filed: March 3, 2003
    Publication date: September 4, 2003
    Inventors: Narihito Kojima, Ryuta Takeichi, Akiyo Nakajima, Hiroshi Nagame, Yohta Sakon