Patents by Inventor Tadayoshi Uchida

Tadayoshi Uchida 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: 11016403
    Abstract: An electrophotographic photoconductor is provided that includes a conductive substrate, an undercoat layer overlying the conductive substrate, and a photosensitive layer overlying the undercoat layer. The undercoat layer contains zinc oxide particles and a binder resin and has a volume resistivity of 0.03×106 ?·cm or less in an electrical field of 5 V/?m at a temperature of 23 degrees C. and a relative humidity of 55%. The photosensitive layer contains a compound represented by the following general formula (1): where each of R1 to R3 independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms.
    Type: Grant
    Filed: January 15, 2020
    Date of Patent: May 25, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideki Nakamura, Tadayoshi Uchida, Shuya Sugimoto, Mitsuaki Hirose, Noboru Toriu, Kaori Harada
  • Publication number: 20200233325
    Abstract: An electrophotographic photoconductor is provided that includes a conductive substrate, an undercoat layer overlying the conductive substrate, and a photosensitive layer overlying the undercoat layer. The undercoat layer contains zinc oxide particles and a binder resin and has a volume resistivity of 0.03×106 ?·cm or less in an electrical field of 5 V/?m at a temperature of 23 degrees C. and a relative humidity of 55%. The photosensitive layer contains a compound represented by the following general formula (1): where each of R1 to R3 independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms which may have a substituent, or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms.
    Type: Application
    Filed: January 15, 2020
    Publication date: July 23, 2020
    Inventors: Hideki Nakamura, Tadayoshi Uchida, Shuya Sugimoto, Mitsuaki Hirose, Noboru Toriu, Kaori Harada
  • Patent number: 9535344
    Abstract: A photoconductor is used for an image-forming apparatus, and the photoconductor has a surface including irregularities having an arithmetic average roughness of 0.1 ?m or more and 0.5 ?m or less in a cycle length from 867 to 1,654 ?m.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: January 3, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Noboru Toriu, Hideki Nakamura, Tadayoshi Uchida, Hiroki Orii
  • Publication number: 20160187792
    Abstract: A photoconductor is used for an image-forming apparatus, and the photoconductor has a surface including irregularities having an arithmetic average roughness of 0.1 ?m or more and 0.5 ?m or less in a cycle length from 867 to 1,654 ?m.
    Type: Application
    Filed: December 18, 2015
    Publication date: June 30, 2016
    Inventors: Noboru TORIU, Hideki NAKAMURA, Tadayoshi UCHIDA, Hiroki ORll
  • Patent number: 8932787
    Abstract: An electrophotographic photoconductor including: an electroconductive substrate; an intermediate layer; and a photoconductive layer, the intermediate layer and the photoconductive layer being on the electroconductive substrate, wherein the intermediate layer includes an inorganic pigment and a binder resin, wherein a volume ratio of the inorganic pigment in the intermediate layer is 30% by volume to 50% by volume, wherein the inorganic pigment comprises titanium oxide and a content of the titanium oxide in the inorganic pigment is 70% by mass to 90% by mass, wherein the inorganic pigment has a specific surface area of 70 m2/g to 140 m2/g, and wherein the intermediate layer has a volume resistivity at an electrical field intensity of 2.5×105 V/cm of 5×1011 ?·cm to 1×1013 ?·cm.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: January 13, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Eiji Kurimoto, Tadayoshi Uchida, Hideki Nakamura
  • Publication number: 20130157181
    Abstract: An electrophotographic photoconductor including: an electroconductive substrate; an intermediate layer; and a photoconductive layer, the intermediate layer and the photoconductive layer being on the electroconductive substrate, wherein the intermediate layer includes an inorganic pigment and a binder resin, wherein a volume ratio of the inorganic pigment in the intermediate layer is 30% by volume to 50% by volume, wherein the inorganic pigment comprises titanium oxide and a content of the titanium oxide in the inorganic pigment is 70% by mass to 90% by mass, wherein the inorganic pigment has a specific surface area of 70 m2/g to 140 m2/g, and wherein the intermediate layer has a volume resistivity at an electrical field intensity of 2.5×105 V/cm of 5×1011 ?·cm to 1×1013 ?·cm.
    Type: Application
    Filed: December 14, 2012
    Publication date: June 20, 2013
    Inventors: Eiji Kurimoto, Tadayoshi Uchida, Hideki Nakamura
  • Patent number: 8278016
    Abstract: An electrophotographic photoconductor including an electroconductive support and a photoconductive layer provided thereon, wherein the photoconductive layer includes a charge generating material, an electron transporting material and a hole transporting material, the electron transporting material being a diphenoquinone compound represented by formula (1) described herein, the hole transporting material being a compound represented by formula (2) described herein.
    Type: Grant
    Filed: June 9, 2009
    Date of Patent: October 2, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Keisuke Shimoyama, Eiji Kurimoto, Takaaki Ikegami, Kohsuke Yamamoto, Tadayoshi Uchida, Takumi Shinohara, Hajime Suzuki
  • Patent number: 8257891
    Abstract: To provide an electrophotographic photoconductor including: a substrate; a charge generating layer; and a charge transporting layer, the charge generating layer and the charge transporting layer being disposed over the substrate, wherein the charge transporting layer contains a charge transporting material represented by General Formula (I) below and an additive represented by General Formula (II) below: where R1, R2 and R3 each independently denote any one of a hydrogen atom, a halogen atom, an alkyl group which may contain a substituent, and an alkoxy group which may contain a substituent, where R4 and R5 each denote a tertiary butyl group, and R6 and R7 each independently denote one of an alkyl group which may contain a substituent, and an aryl group which may contain a substituent.
    Type: Grant
    Filed: January 8, 2010
    Date of Patent: September 4, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Naoki Nakatake, Atsushi Takehara, Toshihiko Koizumi, Tsuyoshi Ueda, Tadayoshi Uchida, Hajime Suzuki
  • Publication number: 20100178074
    Abstract: To provide an electrophotographic photoconductor including: a substrate; a charge generating layer; and a charge transporting layer, the charge generating layer and the charge transporting layer being disposed over the substrate, wherein the charge transporting layer contains a charge transporting material represented by General Formula (I) below and an additive represented by General Formula (II) below: where R1, R2 and R3 each independently denote any one of a hydrogen atom, a halogen atom, an alkyl group which may contain a substituent, and an alkoxy group which may contain a substituent, where R4 and R5 each denote a tertiary butyl group, and R6 and R7 each independently denote one of an alkyl group which may contain a substituent, and an aryl group which may contain a substituent.
    Type: Application
    Filed: January 8, 2010
    Publication date: July 15, 2010
    Applicant: RICOH COMPANY, LTD.
    Inventors: Naoki NAKATAKE, Atsushi Takehara, Toshihiko Koizumi, Tsuyoshi Ueda, Tadayoshi Uchida, Hajime Suzuki
  • Publication number: 20090311616
    Abstract: An electrophotographic photoconductor including an electroconductive support and a photoconductive layer provided thereon, wherein the photoconductive layer includes a charge generating material, an electron transporting material and a hole transporting material, the electron transporting material being a diphenoquinone compound represented by formula (1) described herein, the hole transporting material being a compound represented by formula (2) described herein.
    Type: Application
    Filed: June 9, 2009
    Publication date: December 17, 2009
    Inventors: Keisuke SHIMOYAMA, Eiji KURIMOTO, Takaaki IKEGAMI, Kohsuke YAMAMOTO, Tadayoshi UCHIDA, Takumi SHINOHARA, Hajime SUZUKI
  • Patent number: 7629096
    Abstract: An electrophotographic photoreceptor that without detriment to excellent electrophotographic performance, realizes coating of any defects on a conductive substrate and excels in repetition stability and environmental performance. There is provided an electrophotographic photoreceptor having a photoreceptive layer superimposed via an undercoat layer on a conductive support, characterized in that the undercoat layer contains a polyimide resin and that at least one of the compounds of the following formulae is contained as a charge transfer agent of the photoreceptive layer.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: December 8, 2009
    Assignee: Yamanashi Electronics Co., Ltd.
    Inventors: Hajime Suzuki, Tadayoshi Uchida, Ryoji Kobayashi
  • Publication number: 20070154826
    Abstract: The present invention relates to an electrophotographic photoreceptor used for electrophotographic apparatuses such as copying machines, LED, LD printers, etc. and particularly to an electrophotographic photoreceptor which has an undercoat layer and uses an organic photoconductive material, and an electrophotographic apparatus provided with the photoreceptor.
    Type: Application
    Filed: December 21, 2004
    Publication date: July 5, 2007
    Applicants: Shindengen Electric MFG. Co., Ltd., Yamanashi Electrics, Co., Ltd.
    Inventors: Hajime Suzuki, Tadayoshi Uchida, Ryoji Kobayashi
  • Publication number: 20070148574
    Abstract: An electrophotographic photoreceptor that without detriment to excellent electrophotographic performance, realizes coating of any defects on a conductive substrate and excels in repetition stability and environmental performance. There is provided an electrophotographic photoreceptor having a photoreceptive layer superimposed via an undercoat layer on a conductive support, characterized in that the undercoat layer contains a polyimide resin and that at least one of the compounds of the following formulae is contained as a charge transfer agent of the photoreceptive layer.
    Type: Application
    Filed: December 21, 2004
    Publication date: June 28, 2007
    Inventors: Hajime Suzuki, Tadayoshi Uchida, Ryoji Kobayashi