Patents by Inventor Yosuke Morikawa

Yosuke Morikawa 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: 20030175604
    Abstract: In an electrophotographic photosensitive member comprising a conductive support, and provided thereon a charge generation layer, a charge transport layer and a protective layer in this order, the layer thickness a0 (&mgr;m) of the charge transport layer at the middle portion of the conductive support in its generatrix direction, the layer thickness b0 (&mgr;m) of the protective layer at the middle portion of the conductive support in its generatrix direction, the layer thickness a (&mgr;m) of the charge transport layer at a portion other than the middle portion and the layer thickness b (&mgr;m) of the protective layer at the portion other than the middle portion satisfy the following expression (1) in a region satisfying 0.8 (&mgr;m)≦(a0−a)≦3.
    Type: Application
    Filed: December 18, 2002
    Publication date: September 18, 2003
    Inventors: Yosuke Morikawa, Tatsuya Ikezue, Kouichi Nakata, Kimihiro Yoshimura, Daisuke Tanaka
  • Publication number: 20030099488
    Abstract: An electrophotographic apparatus and a process cartridge have a charge unit for charging the surface of a photosensitive member by direct injection of electrical charge from a contact charging member to the photosensitive member. The charging unit also functions as a unit for supporting residual toner on the surface of the photosensitive member after transfer, for normalizing the electrical charge of the residual toner, and for returning the normalized residual toner to the surface of the photosensitive member. A developing unit also functions as a unit for recovering the normalized residual toner returned to the surface of the photosensitive member. The absolute value of the difference in charged potential between a first rotation and a second rotation of the photosensitive member is higher than 5 V and lower than 70 V.
    Type: Application
    Filed: June 19, 2002
    Publication date: May 29, 2003
    Inventors: Daisuke Tanaka, Yosuke Morikawa, Kouichi Nakata, Kimihiro Yoshimura
  • Patent number: 6562530
    Abstract: An electrophotographic photosensitive member has, in this order, a support, a photosensitive layer and a protective layer. The thickness d (&mgr;m) of the protective layer, the universal hardness Hu-1 (N/mm2) of the protective layer, and the universal hardness Hu-2 (N/mm2) of the photosensitive layer after peeling off the protective layer satisfy the following expression (1): 5.8×d+Hu-2≦Hu-1≦−2.45×d2+44.4×d+Hu-2  (1). Also disclosed are a process cartridge and an electrophotographic apparatus which have the above electrophotographic photosensitive member.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: May 13, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yosuke Morikawa, Kouichi Nakata, Kimihiro Yoshimura, Daisuke Tanaka
  • Patent number: 6555279
    Abstract: An electrophotographic photosensitive member exhibiting a good durability and stable electrophotographic performances regardless of environmental change is provided by coating the photosensitive layer with a specific protective layer. The protective layer comprises a cured phenolic resin and a charge-transporting compound having at least one group selected from the group consisting of hydroxyalkyl groups, hydroxyalkoxy groups and hydroxyphenyl groups capable of having a substituent.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: April 29, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kouichi Nakata, Yosuke Morikawa, Kimihiro Yoshimura, Hiroshi Saito
  • Publication number: 20030021612
    Abstract: An electrophotographic apparatus, includes: an electrophotographic photosensitive member and a charging device. The charging device includes a conductor particle-carrying member having an electroconductive and elastic surface, and conductor particles having a particle size of 10 nm-10 &mgr;m and carried on the carrying member so as to be disposed in contact with the photosensitive member, thereby directly injecting charges to the photosensitive member to charge the photosensitive member.
    Type: Application
    Filed: June 18, 2002
    Publication date: January 30, 2003
    Applicant: CANON KABISHIKI KAISHA
    Inventors: Yosuke Morikawa, Kouichi Nakata, Kimihiro Yoshimura, Daisuke Tanaka
  • Patent number: 6492081
    Abstract: An electrophotographic photosensitive member exhibiting a good durability and stable electrophotographic performances regardless of environmental change is provided by coating the photosensitive layer with a specific protective layer. The protective layer has a thickness of 1-7 &mgr;m and comprises a cured phenolic resin and metal particles or metal oxide particles dispersed therein.
    Type: Grant
    Filed: June 19, 2001
    Date of Patent: December 10, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yosuke Morikawa, Kouichi Nakata, Hiroshi Saito
  • Publication number: 20020119382
    Abstract: An electrophotographic photosensitive member exhibiting a good durability and stable electrophotographic performances regardless of environmental change is provided by coating the photosensitive layer with a specific protective layer. The protective layer comprises a cured phenolic resin and a charge-transporting compound having at least one group selected from the group consisting of hydroxyalkyl groups, hydroxyalkoxy groups and hydroxyphenyl groups capable of having a substituent.
    Type: Application
    Filed: June 21, 2001
    Publication date: August 29, 2002
    Inventors: Kouichi Nakata, Yosuke Morikawa, Kimihiro Yoshimura, Hiroshi Saito
  • Patent number: 6434351
    Abstract: An electrophotographic photosensitive member is disclosed which has a photosensitive layer containing an organic charge-generating material and an organic charge-transporting material, and a surface layer containing electroconductive particles, and is charged electrically by a charging member placed in contact therewith. The photosensitive member has an electrostatic capacity of not less than 130 pF/cm2. Also, a process cartridge and an employing the photosensitive member are disclosed.
    Type: Grant
    Filed: June 14, 2001
    Date of Patent: August 13, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yosuke Morikawa, Hiroyuki Tanaka
  • Publication number: 20020045116
    Abstract: An electrophotographic photosensitive member has, in this order, a support, a photosensitive layer and a protective layer.
    Type: Application
    Filed: June 19, 2001
    Publication date: April 18, 2002
    Inventors: Yosuke Morikawa, Kouichi Nakata, Kimihiro Yoshimura, Daisuke Tanaka
  • Publication number: 20020034701
    Abstract: An electrophotographic photosensitive member exhibiting a good durability and stable electrophotographic performances regardless of environmental change is provided by coating the photosensitive layer with a specific protective layer. The protective layer has a thickness of 1-7 &mgr;m and comprises a cured phenolic resin and metal particles or metal oxide particles dispersed therein.
    Type: Application
    Filed: June 19, 2001
    Publication date: March 21, 2002
    Inventors: Yosuke Morikawa, Kouichi Nakata, Hiroshi Saito
  • Publication number: 20010051060
    Abstract: An electrophotographic photosensitive member is disclosed which has a photosensitive layer containing an organic charge-generating material and an organic charge-transporting material, and a surface layer containing electroconductive particles, and is charged electrically by a charging member placed in contact therewith. The photosensitive member has an electrostatic capacity of not less than 130 pF/cm2. Also, a process cartridge and an employing the photosensitive member are disclosed.
    Type: Application
    Filed: June 14, 2001
    Publication date: December 13, 2001
    Inventors: Yosuke Morikawa, Hiroyuki Tanaka
  • Patent number: 6324365
    Abstract: An electrophotographic photosensitive member is disclosed which has a photosensitive layer containing an organic charge-generating material and an organic charge-transporting material, and a surface layer containing electroconductive particles, and is charged electrically by a charging member placed in contact therewith. The photosensitive member has an electrostatic capacity of not less than 130 pF/cm2. Also, a process cartridge and an employing the photosensitive member are disclosed.
    Type: Grant
    Filed: May 28, 1997
    Date of Patent: November 27, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yosuke Morikawa, Hiroyuki Tanaka