Patents by Inventor Hirokazu Sakashita

Hirokazu Sakashita 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).

  • Electrophotographic photoreceptor, image forming apparatus and process cartridge
    Patent number: 8685600
    Abstract: There is provided an electrophotographic photoreceptor including a conductive substrate; an intermediate layer; a photosensitive layer; and a surface layer, in this order, the surface layer including two or more charge transporting materials each including a reactive substituent and respectively having mutually different ionization potentials, in an amount of 90% by weight or more relative to the total solid content of the surface layer, and the content ratio X of each of the two or more charge transporting materials satisfying the following Formula (1).
    Type: Grant
    Filed: November 23, 2009
    Date of Patent: April 1, 2014
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hirofumi Nakamura, Keiko Matsuki, Shingo Hirahara, Takanori Suga, Daisuke Haruyama, Hirokazu Sakashita, Masahiro Iwasaki, Takayuki Yamashita, Mitsuhide Nakamura
  • ELECTROPHOTOGRAPHIC PHOTORECEPTOR, IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE
    Publication number: 20100330472
    Abstract: There is provided an electrophotographic photoreceptor including a conductive substrate; an intermediate layer; a photosensitive layer; and a surface layer, in this order, the surface layer including two or more charge transporting materials each including a reactive substituent and respectively having mutually different ionization potentials, in an amount of 90% by weight or more relative to the total solid content of the surface layer, and the content ratio X of each of the two or more charge transporting materials satisfying the following Formula (1).
    Type: Application
    Filed: November 23, 2009
    Publication date: December 30, 2010
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Hirofumi NAKAMURA, Keiko MATSUKI, Shingo HIRAHARA, Takanori SUGA, Daisuke HARUYAMA, Hirokazu SAKASHITA, Masahiro IWASAKI, Takayuki YAMASHITA, Mitsuhide NAKAMURA
  • Electrophotographic photoreceptor, process cartridge and electrophotographic apparatus
    Patent number: 7592112
    Abstract: A multilayer electrophotographic photoreceptor, comprising an electroconductive substrate, and at least an interlayer and a charge-generating layer formed on the substrate, wherein the interlayer comprises fine metal oxide particles and the interlayer and the charge-generating layer comprise anthraquinone derivative(s), and wherein the interlayer has a volume resistivity in a range of 1.0×108 ?·cm to 1.0×1013 ?·cm when an electric field of 106 V/m is applied thereto at 28° C. and 85% relative humidity. A process cartridge and an image forming apparatus using the multilayer electrophotographic photoreceptor are also provided.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: September 22, 2009
    Assignees: Fuji Xerox Co., Ltd., Xerox Corporation
    Inventors: Shigeaki Shiino, Makoto Takemoto, Makoto Kusayanagi, Koichi Yasaku, Hirokazu Sakashita, Makoto Nishimura, Yu Qi, Nan-Xing Hu, Ah-Mee Hor
  • Electrophotographic photoreceptor, process cartridge and electrophotographic apparatus
    Publication number: 20060014090
    Abstract: A multilayer electrophotographic photoreceptor, comprising an electroconductive substrate, and at least an interlayer and a charge-generating layer formed on the substrate, wherein the interlayer comprises fine metal oxide particles and the interlayer and the charge-generating layer comprise anthiaquinone derivative(s), and wherein the interlayer has a volume resistivity in a range of 1.0×108 ?·cm to 1.0×1013 ?·cm when an electric field of 106 V/m is applied thereto at 28° C. and 85% relative humidity. A process cartridge and an image forming apparatus using the multilayer electrophotographic photoreceptor are also provided.
    Type: Application
    Filed: March 18, 2005
    Publication date: January 19, 2006
    Applicants: Fuji Xerox Co., Ltd., Xerox Corporation
    Inventors: Shigeaki Shiino, Makoto Takemoto, Makoto Kusayanagi, Koichi Yasaku, Hirokazu Sakashita, Makoto Nishimura, Yu Qi, Nan-Xing Hu, Ah-Mee Hor