Patents by Inventor Yuka Ishiduka

Yuka Ishiduka 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).

  • Publication number: 20140004452
    Abstract: An electrophotographic photosensitive member has a laminated body and a hole transporting layer formed on the laminated body, wherein the laminated body has a support, an electron transporting layer and a charge generating layer in this order, and satisfies the following expressions (2) and (4): |Vl2?Vl1|?0.35??(2) 0.10?|(Vd2?Vl3)/Vd2|?0.20??(4).
    Type: Application
    Filed: June 28, 2013
    Publication date: January 2, 2014
    Inventors: Michiyo Sekiya, Kunihiko Sekido, Atsushi Okuda, Hiroyuki Tomono, Nobuhiro Nakamura, Yota Ito, Kenichi Kaku, Yuka Ishiduka
  • Publication number: 20140004451
    Abstract: An electrophotographic photosensitive member includes an undercoat layer having a structure represented by formula (1).
    Type: Application
    Filed: June 28, 2013
    Publication date: January 2, 2014
    Inventors: Hiroyuki Tomono, Kunihiko Sekido, Michiyo Sekiya, Atsushi Okuda, Yuka Ishiduka, Nobuhiro Nakamura, Yota Ito
  • Publication number: 20140004453
    Abstract: An electrophotographic photosensitive member has a laminated body, and a hole transporting layer formed on the laminated body, wherein the laminated body is a laminated body having a conductive support, an electron transporting layer and a charge generating layer. When an impedance is measured by forming a circular-shaped gold electrode having a thickness of 300 nm and a diameter of 10 mm on a surface of the charge generating layer of the laminated body by sputtering, and applying an alternating electric field of 100 mV and 0.1 Hz between the conductive support and the gold electrode, the laminated body of the electrophotographic photosensitive member satisfies the following expression (1): R_opt/R_dark?0.
    Type: Application
    Filed: June 28, 2013
    Publication date: January 2, 2014
    Inventors: Kenichi Kaku, Michiyo Sekiya, Kunihiko Sekido, Atsushi Okuda, Nobuhiro Nakamura, Yota Ito, Hiroyuki Tomono, Yuka Ishiduka
  • Publication number: 20140004456
    Abstract: An undercoat layer of an electrophotographic photosensitive member contains a polymerized product of (cured material) a composition that contains a particular crosslinking agent, a particular resin, and a particular charge transporting substance.
    Type: Application
    Filed: June 28, 2013
    Publication date: January 2, 2014
    Inventors: Atsushi Okuda, Nobuhiro Nakamura, Kunihiko Sekido, Michiyo Sekiya, Yota Ito, Kenichi Kaku, Hiroyuki Tomono, Yuka Ishiduka
  • Publication number: 20140004450
    Abstract: Provided is an electrophotographic photosensitive member in which an undercoat layer is a layer of which at least one selected from the group consisting of a compound represented by the formula (1), a compound represented by the formula (2), a compound represented by the formula (3) and a compound represented by the formula (4) can be detected by gas chromatography analysis when the undercoat layer is heated at 150° C. for 60 minutes by headspace method.
    Type: Application
    Filed: June 10, 2013
    Publication date: January 2, 2014
    Inventors: Ryoichi Tokimitsu, Yuka Ishiduka, Wataru Kitamura, Kenichi Kaku, Mai Murakami
  • Publication number: 20140004455
    Abstract: An undercoat layer of an electrophotographic photosensitive member contains a polymerized product of a composition that contains an isocyanate compound having a specific structure, a resin having a specific structure, and an electron transporting substance having a specific structure.
    Type: Application
    Filed: June 28, 2013
    Publication date: January 2, 2014
    Inventors: Kunihiko Sekido, Hiroyuki Tomono, Michiyo Sekiya, Atsushi Okuda, Yuka Ishiduka, Nobuhiro Nakamura, Yota Ito
  • Patent number: 8512922
    Abstract: Aspects of the present invention provide an electrophotographic photosensitive member in which an intermediate layer contains metal oxide particles, an organic resin, and a specific compound (fluorenone derivative), and a process cartridge and an electrophotographic apparatus including the electrophotographic photosensitive member.
    Type: Grant
    Filed: October 12, 2010
    Date of Patent: August 20, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuka Ishiduka, Wataru Kitamura, Kenichi Kaku, Mai Murakami
  • Patent number: 8481236
    Abstract: An electrophotographic photosensitive member is provided in which both a long-term potential variation and a short-term potential variation are suppressed, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member are also provided. The intermediate layer of the electrophotographic photosensitive member includes an organic resin and rutile-type titanium oxide crystal particles which contain tin and have an average primary particle diameter of 3 nm or more and 9 nm or less.
    Type: Grant
    Filed: April 20, 2010
    Date of Patent: July 9, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masato Tanaka, Yuka Ishiduka
  • Publication number: 20120033994
    Abstract: An electrophotographic photosensitive member is provided in which both a long-term potential variation and a short-term potential variation are suppressed, a method for producing the electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member are also provided. An intermediate layer of the electrophotographic photosensitive member is formed by applying a coating liquid for the intermediate layer, which contains an organic resin and a rutile-type acidic titania sol containing tin, and drying the applied coating liquid.
    Type: Application
    Filed: April 20, 2010
    Publication date: February 9, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masato Tanaka, Yuka Ishiduka
  • Patent number: 8088541
    Abstract: The present invention relates to a polyvinyl acetal resin having a specific repeating structural unit, an electrophotographic photosensitive member using the polyvinyl acetal resin, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: January 3, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masato Tanaka, Atsushi Fujii, Yuka Ishiduka, Masataka Kawahara, Masaki Nonaka
  • Publication number: 20110293323
    Abstract: An electrophotographic photosensitive member is provided in which both a long-term potential variation and a short-term potential variation are suppressed, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member are also provided. The intermediate layer of the electrophotographic photosensitive member includes an organic resin and rutile-type titanium oxide crystal particles which contain tin and have an average primary particle diameter of 3 nm or more and 9 nm or less.
    Type: Application
    Filed: April 20, 2010
    Publication date: December 1, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masato Tanaka, Yuka Ishiduka
  • Publication number: 20110117483
    Abstract: Aspects of the present invention provide an electrophotographic photosensitive member in which an intermediate layer contains metal oxide particles, an organic resin, and a specific compound (fluorenone derivative), and a process cartridge and an electrophotographic apparatus including the electrophotographic photosensitive member.
    Type: Application
    Filed: October 12, 2010
    Publication date: May 19, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Yuka Ishiduka, Wataru Kitamura, Kenichi Kaku, Mai Murakami
  • Patent number: 7910274
    Abstract: An electrophotographic photosensitive member is provided in which both a potential variation over a long time period and a potential variation within a short time period are suppressed. A method of producing the electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member are also provided. In the electrophotographic photosensitive member, an intermediate layer is a layer formed by coating and drying a coating liquid for an intermediate layer, containing an acidic titania sol and an organic resin, and the acidic titania sol is an acidic sol containing anatase-type titanium oxide crystal particles having an average primary particle diameter of 3 nm or more and 9 nm or less.
    Type: Grant
    Filed: April 27, 2009
    Date of Patent: March 22, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masato Tanaka, Takehiko Endo, Atsushi Fujii, Kenichi Kaku, Yuka Ishiduka, Masaki Nonaka
  • Publication number: 20090208247
    Abstract: An electrophotographic photosensitive member is provided in which both a potential variation over a long time period and a potential variation within a short time period are suppressed. A method of producing the electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member are also provided. In the electrophotographic photosensitive member, an intermediate layer is a layer formed by coating and drying a coating liquid for an intermediate layer, containing an acidic titania sol and an organic resin, and the acidic titania sol is an acidic sol containing anatase-type titanium oxide crystal particles having an average primary particle diameter of 3 nm or more and 9 nm or less.
    Type: Application
    Filed: April 27, 2009
    Publication date: August 20, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masato Tanaka, Takehiko Endo, Atsushi Fujii, Kenichi Kaku, Yuka Ishiduka, Masaki Nonaka
  • Publication number: 20090123176
    Abstract: The present invention relates to a polyvinyl acetal resin having a specific repeating structural unit, an electrophotographic photosensitive member using the polyvinyl acetal resin, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member.
    Type: Application
    Filed: December 5, 2006
    Publication date: May 14, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masato Tanaka, Atsushi Fujii, Yuka Ishiduka, Masataka Kawahara, Masaki Nonaka
  • Patent number: 7009080
    Abstract: A process for producing a halogenated aromatic amine compound by allowing an aromatic amine compound to react with a dihalogenated aromatic compound in the presence of i) a metallic catalyst having a phosphorus-containing ligand having at least one cyclic hydrocarbon group and ii) a basic compound in a non-reactive solvent.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: March 7, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Harunobu Ogaki, Takakazu Tanaka, Itaru Takaya, Yuka Ishiduka
  • Patent number: 7001699
    Abstract: In an electrophotographic photosensitive member having a support, and provided thereon a photosensitive layer, a surface layer of the electrophotographic photosensitive member contains an electrically insulating binder resin and a random-copolymer type high-molecular-weight charge-transporting material having two kinds of specific repeating structural units. Also disclosed are a process cartridge and an electrophotographic apparatus which have such an electrophotographic photosensitive member.
    Type: Grant
    Filed: August 26, 2003
    Date of Patent: February 21, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takakazu Tanaka, Akira Yoshida, Hidetoshi Hirano, Yuka Ishiduka, Harunobu Ogaki
  • Patent number: 6994941
    Abstract: An electrophotographic photosensitive member is provided having a support and a photosensitive layer provided on the support and containing at least one kind of charge-transporting material which has a specific structure with a molecular weight of from 1,500 to 4,000, and is held in a proportion of from 90% by weight to 100% by weight based on the total weight of the charge-transporting material.
    Type: Grant
    Filed: August 28, 2003
    Date of Patent: February 7, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takakazu Tanaka, Itaru Takaya, Yuka Ishiduka, Harunobu Ogaki, Kenichi Kaku
  • Patent number: 6991881
    Abstract: The present invention relates to an electrophotographic photosensitive member having a support and provided thereon a photosensitive layer. The photosensitive layer contains a high-molecular weight charge-transporting material having a specific repeating structural unit. The high-molecular weight charge-transporting material has a weight-average molecular weight Mw of 1,500 or more and an energy level of highest occupied molecular orbital, EHOMO, of from ?8.3 eV or more to ?8.0 eV or less as found by semiempirical molecular-orbital calculation. The present invention also relates to a process cartridge and an electrophotographic apparatus which have such an electrophotographic photosensitive member.
    Type: Grant
    Filed: April 25, 2003
    Date of Patent: January 31, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Harunobu Ogaki, Akira Yoshida, Takakazu Tanaka, Itaru Takaya, Yuka Ishiduka
  • Publication number: 20050208402
    Abstract: An electrophotographic photosensitive member is provided having a support and a photosensitive layer provided on the support and containing at least one kind of charge-transporting material which has a specific structure with a molecular weight of from 1,500 to 4,000, and is held in a proportion of from 90% by weight to 100% by weight based on the total weight of the charge-transporting material.
    Type: Application
    Filed: May 16, 2005
    Publication date: September 22, 2005
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Takakazu Tanaka, Itaru Takaya, Yuka Ishiduka, Harunobu Ogaki, Kenichi Kaku