Patents by Inventor Kazuhiro Yamauchi

Kazuhiro Yamauchi 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: 9651888
    Abstract: The electroconductive member has an electroconductive support and a surface layer formed on the electroconductive support, wherein the surface layer has a porous body having a continuous open pore, and the electroconductive member satisfies the following (1) and (2): (1) in a specific condition, a surface potential of the electroconductive member, after an elapse of 10 seconds since a completion of a discharge is 10 V or more; and (2) when applying a direct voltage between a polyethylene terephthalate film as a member to be charged and the electroconductive member, and charging the polyethylene terephthalate film, |Vd|?|Vin|?|Vth| is satisfied within a range of |Vin|>|Vth|, wherein, Vd represents a charge potential of the polyethylene terephthalate film, Vin represents a voltage applied between the electroconductive member and the polyethylene terephthalate film, Vth represents a discharge starting voltage.
    Type: Grant
    Filed: September 19, 2014
    Date of Patent: May 16, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Norifumi Muranaka, Kazuhiro Yamauchi, Yuichi Kikuchi, Koji Otsuka, Masaki Imoto, Tetsuo Hino, Satoru Nishioka
  • Publication number: 20170130366
    Abstract: In a nanofiber structure in which a nanofiber A and a nanofiber B are tangled with each other, the softening point of the nanofiber A is different from that of the nanofiber B, a cross-section along a surface of the nanofiber A orthogonal to a longitudinal direction thereof has a shape having a concave portion, and the nanofiber A and the nanofiber B are fused with each other at this concave portion.
    Type: Application
    Filed: November 3, 2016
    Publication date: May 11, 2017
    Inventors: Kaori Yasufuku, Tetsuo Hino, Kenji Takashima, Kazuhiro Yamauchi
  • Patent number: 9639009
    Abstract: The present invention provides a highly electro-conductive electrophotographic member which contributes to formation of high-quality electrophotographic images while bleeding out of an ion conducting agent is reduced, a process cartridge, and an electrophotographic apparatus. Accordingly, the electrophotographic member according to the present invention includes an electro-conductive mandrel and an electro-conductive layer, wherein the electro-conductive layer contains a resin synthesized from a nitrogen-containing aromatic heterocyclic cation and a compound being able to react with the nitrogen-containing aromatic heterocyclic cation, and an anion; the nitrogen-containing aromatic heterocyclic cation has two substituents bonded to hydroxyl groups; and the substituent bonded to the hydroxyl group is bonded to a nitrogen atom of a nitrogen-containing aromatic heterocycle of the nitrogen-containing aromatic heterocyclic cation.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: May 2, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Sosuke Yamaguchi, Masaki Yamada, Hideya Arimura, Kazuhiro Yamauchi, Satoru Nishioka
  • Patent number: 9625838
    Abstract: An electrophotographic apparatus includes a cylindrical electrophotographic photosensitive member, a charging roller that is disposed in contact with the electrophotographic photosensitive member and applies a direct current voltage to charge the electrophotographic photosensitive member, and a driving force transmission that transmits a driving force which causes rotation so that contact portions of the electrophotographic photosensitive member and the charging roller move in the same direction and the peripheral speed of the charging roller is higher than the peripheral speed of the electrophotographic photosensitive member, wherein the undercoat layer of the electrophotographic photosensitive member contains metal oxide and the undercoat layer has a volume resistivity of 1×107 ?·cm or more and 1×1014 ?·cm or less.
    Type: Grant
    Filed: November 23, 2015
    Date of Patent: April 18, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazumichi Sugiyama, Daisuke Tanaka, Takeshi Murakami, Daisuke Kawaguchi, Kazuhiro Yamauchi, Satoru Nishioka
  • Publication number: 20170100687
    Abstract: Provided is a nanofiber accumulated body having a high mechanical strength and excellent in durability, the polymer nanofiber accumulated body including polymer nanofibers each containing a polymer material, the polymer nanofibers being accumulated and three-dimensionally entangled with each other to form the accumulated body, in which: the polymer nanofibers each have a fiber diameter of 3 ?m or less; and the polymer nanofibers each contain 5 wt % to 30 wt % of a low-molecular weight organic compound having at least one ?,?-unsaturated ester structure, with respect to a total weight of the polymer nanofibers.
    Type: Application
    Filed: September 16, 2016
    Publication date: April 13, 2017
    Inventors: Tetsuo Hino, Kaori Yasufuku, Kenji Takashima, Kazuhiro Yamauchi
  • Publication number: 20170102633
    Abstract: An electrophotographic electro-conductive member comprising an electro-conductive mandrel and an electro-conductive elastic layer on the electro-conductive mandrel, wherein the electro-conductive elastic layer has an elastic coefficient of 1 MPa or more and 100 MPa or less, as well as a matrix containing first rubber and a plurality of electro-conductive domains dispersed in the matrix. Each of the electro-conductive domains contains an electro-conductive particle, and the electro-conductive elastic layer includes regions containing second rubber in the circumferences of the electro-conductive domains. The matrix has an elastic coefficient R1, the regions containing second rubber have an elastic coefficient R2, and the elastic coefficients R1 and R2 satisfy a relationship: R1<R2.
    Type: Application
    Filed: October 4, 2016
    Publication date: April 13, 2017
    Inventors: Takeshi Yoshidome, Saki Tominaga, Yasuhiro Fushimoto, Norifumi Muranaka, Kazuhiro Yamauchi
  • Publication number: 20170090329
    Abstract: An electrophotographic charging member in which the adhesion of contamination is more suppressed is provided. The electrophotographic charging member includes an electro-conductive support and an electro-conductive elastic layer on the electro-conductive support, the electro-conductive elastic layer includes 10% by mass or more and 50% by mass or less of an aggregate of crosslinked rubber particles, the aggregate of the crosslinked rubber particles has a circle-equivalent diameter of 10 ?m or more and 50 ?m or less, the crosslinked rubber particles have one of an acrylic resin and a styrene acrylic resin chemically bonded to a surface thereof, the charging member has a protrusion derived from the aggregate of the crosslinked rubber particles on a surface thereof, and the protrusion has an average height of 50 nm or more and 200 nm or less.
    Type: Application
    Filed: September 15, 2016
    Publication date: March 30, 2017
    Inventors: Kenichi Yamauchi, Kazuhiro Yamauchi, Satoru Nishioka, Hiroki Masu, Noriko Suzumura
  • Patent number: 9599913
    Abstract: An electrophotographic member is provided in which conductivity barely reduces and sufficient conductivity is obtained even under a low temperature and low humidity environment, a reduction in resistance beyond necessity is readily suppressed even under a high temperature and high humidity environment, and the bleeding of the quaternary ammonium salt can be suppressed.
    Type: Grant
    Filed: June 4, 2014
    Date of Patent: March 21, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Satoru Nishioka, Kazuhiro Yamauchi, Masahiro Watanabe, Masaki Yamada, Hideya Arimura
  • Patent number: 9580847
    Abstract: Provided is a porous laminate having satisfactory resistance to a mechanical load such as a bending stress while maintaining the characteristics of a porous structure. A porous laminate includes: a layer A formed on a support, the layer A including a porous film containing polymer nanofibers; and a layer B formed on the layer A, the layer B including a porous film containing polymer nanofibers, in which: an existence ratio of the polymer nanofibers contained in the layer A) is larger than an existence ratio of the polymer nanofibers contained in the layer B; and a difference between the existence ratio of the polymer nanofibers contained in the layer A and the existence ratio of the polymer nanofibers contained in the layer B is more than 40%.
    Type: Grant
    Filed: August 27, 2015
    Date of Patent: February 28, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kenji Takashima, Tetsuo Hino, Kazuhiro Yamauchi
  • Patent number: 9581931
    Abstract: Provided is an electrophotographic member conducive to the formation of a high-quality electrophotographic image, the member showing a small increase in resistance even after long-term electrification under a high-temperature and high-humidity environment, and a process cartridge and an electrophotographic apparatus each including the electrophotographic member as a charging member and/or a developer carrying member. Specifically, provided is an electrophotographic member including a substrate and an electro-conductive layer, in which the electro-conductive layer contains a resin having a structure unit represented by the following structural formula (1) and a specific anion: in the structural formula (1), R1 represents a hydrogen atom or a methyl group, and Z represents a cationic organic group.
    Type: Grant
    Filed: May 11, 2015
    Date of Patent: February 28, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Masaki Yamada, Sosuke Yamaguchi, Kazuhiro Yamauchi, Satoru Nishioka
  • Patent number: 9551949
    Abstract: To suppress an image trouble resulting from abnormal discharge independent of the use conditions and use environment of an electroconductive member, provided is an electroconductive member to be used while being brought into contact with a body to be contacted, the electroconductive member comprising a layer of a network structural body on an outer peripheral surface of a electroconductive support, in which: when a surface of the network structural body in a surface of the electroconductive member is observed, at least a part of the network structural body exists in an arbitrary square region having one side length of 200 ?m; the network structural body contains non-electroconductive fibers; and an average fiber diameter of a top 10% of fiber diameters of the non-electroconductive fibers measured at arbitrary points is 0.2 ?m or more and 15 ?m or less.
    Type: Grant
    Filed: March 24, 2015
    Date of Patent: January 24, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuhiro Yamauchi, Satoru Yamada, Norifumi Muranaka, Yuichi Kikuchi, Tetsuo Hino
  • Patent number: 9547250
    Abstract: The present invention relates to an electroconductive member including an electroconductive support layer and a surface layer formed on a circumference thereof and having a network structure containing fibers, in which an arithmetic mean value dU10 of top 10% fiber diameters is 0.2 ?m or more and 15.0 ?m or less, rigid structural body having a height of 1.0×10?2 to 1.0×101 times as large as a thickness of the surface layer are present on the outer circumferential portion of the electroconductive support layer, and the surface layer satisfies specific conditions.
    Type: Grant
    Filed: March 23, 2015
    Date of Patent: January 17, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuichi Kikuchi, Kazuhiro Yamauchi, Norifumi Muranaka, Satoru Yamada, Tetsuo Hino
  • Patent number: 9541854
    Abstract: Provided is an electroconductive member configured to suppress a void image caused by abnormal discharge and a horizontal streak-like image caused by downstream discharge without depending on the thickness of a photosensitive layer of a photosensitive drum over a long period of time. The electroconductive member for electrophotography comprises at least an electroconductive support and a surface layer formed on an outer side of the electroconductive support. The surface layer includes a porous body and satisfies the predetermined (1), (2), and (3).
    Type: Grant
    Filed: March 23, 2015
    Date of Patent: January 10, 2017
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Yuichi Kikuchi, Kazuhiro Yamauchi, Mikio Shimada, Tetsuo Hino, Masahiro Watanabe, Norifumi Muranaka, Satoru Nishioka
  • Patent number: 9522352
    Abstract: Based on an electrospinning method, a layer A formed of a polymer continuous phase is formed by: setting a potential difference between an ejection portion configured to eject a polymer solution and a collecting portion configured to collect the polymer nanofibers to a voltage value at which the polymer nanofibers can be spun; and setting the potential of the collecting portion to a low value with respect to a ground potential. Next, a layer B formed of polymer nanofibers and a polymer continuous phase is formed by increasing the potential of the collecting portion without stopping the application of voltages to the ejection portion and the collecting portion. Further, a layer C formed of polymer nanofibers is formed by increasing the potential of the collecting portion without stopping the application of the voltages to the ejection portion and the collecting portion.
    Type: Grant
    Filed: March 19, 2015
    Date of Patent: December 20, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kenji Takashima, Tetsuo Hino, Kazuhiro Yamauchi
  • Publication number: 20160347938
    Abstract: Provided is a rubber composition for producing a rubber molded article that is improved in fouling resistance while being reduced in tackiness and frictional force despite the presence of the rubber in its surface. The rubber composition includes: a rubber A; and a plastic B, in which: the rubber A includes a non-fluorine-based rubber material; a difference in elastic modulus between the rubber A and the plastic B is 50 MPa or more; a sea-island structure having a sea portion containing the rubber A and a plurality of island portions each containing the plastic B is formed; the plastic B is contained at a content of more than 0 vol % and 50 vol % or less with respect to a total amount of the rubber A and the plastic B; and 90% or more of the plurality of island portions each have a volume of 4,000 ?m3 or less.
    Type: Application
    Filed: May 11, 2016
    Publication date: December 1, 2016
    Inventors: Kenji Takashima, Tetsuo Hino, Kazuhiro Yamauchi
  • Publication number: 20160296874
    Abstract: Provided is a nanofiber sheet that has a high mechanical strength, is excellent in durability, and has a high specific surface area. The nanofiber sheet includes: a plurality of nanofibers; and a bulk portion produced by bonding of the nanofibers, in which 7×10?3 portion/?m2 or more of the bulk portion satisfying the following formula is contained: 0.5?X2?Y?5 ?m2??(1) where X represents a diameter (?m) of each of the nanofibers and Y represents an area (?m2) of an inscribed circle of the bulk portion when viewed from a surface.
    Type: Application
    Filed: April 5, 2016
    Publication date: October 13, 2016
    Inventors: Kaori Yasufuku, Tetsuo Hino, Kenji Takashima, Kazuhiro Yamauchi
  • Patent number: 9465322
    Abstract: An image forming apparatus includes: an image bearing member; a charging member for electrically charging the image bearing member in contact with the image bearing member; and a developing member for supplying developer in contact with the image bearing member. The developer remaining on the image bearing member after transfer is collected by the developing member. A Martens hardness HMR of a surface of the charging member and a Martens hardness HMD of a surface of the developer satisfy the following relationship: HMD>HMR.
    Type: Grant
    Filed: July 22, 2015
    Date of Patent: October 11, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akihisa Matsukawa, Yusuke Usui, Hiroyoshi Iwayama, Takanori Watanabe, Naoki Okamoto, Kazuhiro Yamauchi
  • Patent number: 9442408
    Abstract: A member for electrophotography for use in forming a high quality electrophotographic image for a long period is provided. The member for electrophotography includes a support, an elastic layer on the support, and a surface layer on the elastic layer. The elastic layer includes a quaternary ammonium salt and an epichlorohydrin rubber. The surface layer includes a material having a specific structure. A universal hardness a surface of the surface layer is 1.0 N/mm2 or more and 5.0 N/mm2 or less.
    Type: Grant
    Filed: November 18, 2015
    Date of Patent: September 13, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuhiro Yamauchi, Kenichi Yamauchi, Satoru Nishioka, Hiroki Masu, Noriko Suzumura
  • Patent number: 9442451
    Abstract: Provided is an electroconductive member for electrophotography which is suppressed in adhesion of a contaminant to a surface thereof. The electroconductive member for electrophotography includes, in this order, an electroconductive support, an electroconductive elastic layer, and a surface layer. The surface layer contains a binder resin and electroconductive fine particles having a number average particle diameter of 5.0 nm or more and 50.0 nm or less. At least part of the electroconductive fine particles are exposed from the surface layer. The surface layer has, on a surface thereof, protruded portions derived from exposed portions of the electroconductive fine particles. The surface layer has a volume resistivity of 1.0×1010 ?cm or more and 1.0×1016 ?cm or less and a universal hardness at a depth of 1 ?m from the surface thereof of 1.0 N/mm2 or more and 7.0 N/mm2 or less.
    Type: Grant
    Filed: November 18, 2015
    Date of Patent: September 13, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kazuhiro Yamauchi, Satoru Nishioka, Kenichi Yamauchi, Hiroki Masu, Noriko Suzumura
  • Publication number: 20160222546
    Abstract: Provided is a glossy member, including: a polymer substrate; and a polymer fiber assembly disposed on the polymer substrate, in which: the polymer fiber assembly has polymer fibers oriented in a given direction; an absolute value of a difference between an average solubility parameter of a constituent material for the polymer substrate and an average solubility parameter of a polymer material of the polymer fibers is less than 5 (J/cm3)1/2; the polymer fibers have an orientation degree of 90% or more; the polymer fibers have fiber diameters of 0.05 ?m or more and 5 ?m or less; and in at least part of a repeating unit structure in the polymer material, a dipole moment is 0 D or more and 3.50 D or less, and an absolute value of a SOMO is 9 eV or more and 12 eV or less.
    Type: Application
    Filed: January 26, 2016
    Publication date: August 4, 2016
    Inventors: Tetsuo Hino, Kenji Takashima, Kazuhiro Yamauchi