Patents by Inventor Hirotaka Yamazaki

Hirotaka Yamazaki 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: 20060146394
    Abstract: In the image display device, in which the image display media are sealed between opposed substrates, at least one of two substrates being transparent, and in which the image display media, to which an electrostatic field is applied, are made to move so as to display an image, a construction of the particles utilizing as the image display media is improved (the first, second, fourth, fifth, sixth, eighth and ninth aspects of the invention), and, a material of the particles utilizing as the image display media is improved (the third, seventh and tenth aspects of the invention). Therefore, the whiteness of the particles and the liquid powder using the particles can be improved, and it is possible to prevent the particle agglutination and to control the charge property. Moreover, in the image display panel in which the particles and the liquid powder are used as the image display media, it is possible to obtain a durability such that a contrast of the image display during a repetition display is not decreased.
    Type: Application
    Filed: April 2, 2004
    Publication date: July 6, 2006
    Applicant: BRIDGESTONE CORPORATION
    Inventors: Norihiko Kaga, Gaku Yakushiji, Hare Tazawa, Maki Masutani, Taichi Kobayashi, Toshiaki Arai, Kazuya Murata, Ryo Sakurai, Yoneji Kobayashi, Hajime Tamura, Hiroyuki Anzai, Hirotaka Yamazaki, Yoichi Nishimuro, Kunio Machida
  • Publication number: 20060087489
    Abstract: An image display device constructed by: an image display means for displaying an image by moving chargeable particles arranged between electrodes by means of a voltage applied to the electrodes; and a light emission means for emitting a light to an image display surface of the image display means (first aspect of the invention).
    Type: Application
    Filed: July 16, 2003
    Publication date: April 27, 2006
    Inventors: Ryou Sakurai, Maki Masutani, Hare Tazawa, Hajime Kitano, Norio Nihei, Hirotaka Yamazaki, Yoshitomo Masuda, Itsuo Tanuma
  • Publication number: 20060087479
    Abstract: In a first aspect of the invention, an image display device, in which one or more groups of particles or liquid powders are sealed between opposed two substrates, at least one of two substrates being transparent, and, in which the particles or the liquid powders, to which an electrostatic field produced by two groups of electrodes having different potentials is applied, are made to move so as to display an image, has a construction such that a member for transmitting a signal, which is applied to circuits for an image display, is provided to the substrate by means of an anisotropic conductive film and members such as the electrode are provided to a substrate opposed to a transparent substrate.
    Type: Application
    Filed: June 20, 2003
    Publication date: April 27, 2006
    Applicant: BRIDGESTONE CORPORATION
    Inventors: Ryou Sakurai, Hajime Kitano, Norio Nihei, Kazuya Murata, Gaku Yakushiji, Norihiko Kaga, Toshiaki Arai, Yoshitomo Masuda, Hirotaka Yamazaki, Hidefumi Kotsubo, Masato Yoshikawa, Shingo Oono, Yoshinori Iwabuchi
  • Publication number: 20050285500
    Abstract: In an image display device which has an image display panel, in which two or more groups of particles or liquid powders having different colors and different charge characteristics are sealed between opposed two substrates, at least one of two substrates being transparent, and, in which the particles or the liquid powders, to which an electrostatic field produced by a pair of electrodes provided on one substrate or both substrates respectively is applied, are made to move so as to display an image, a chip for transmitting a drive signal to the image display panel is arranged in the substrate (first aspect of the invention), or, the two substrates are constructed by a transparent substrate and the pair of electrodes are constructed by a transparent electrode (second aspect of the invention).
    Type: Application
    Filed: July 8, 2003
    Publication date: December 29, 2005
    Inventors: Reiji Hattori, Itsuo Tanuma, Yoshitomo Masuda, Norio Nihei, Ryou Sakurai, Hajime Tamura, Hirotaka Yamazaki
  • Patent number: 6818674
    Abstract: There are disclosed an elastic member which comprises (A) polyurethane foam obtained by agitationally mixing a foaming agent, a foam stabiizer and a urethane prepolymer synthesized from a polyol and a polyisocyanate in the presence of a modified silicone, or (B) polyurethane foam obtained by agitationally mixing a polyol, a polyisocyanate, a modified silicone oil bearing a functional group reactive with a polyisocyanate, a foaming agent and a foam stabiizer comprising a polyether modified silicone containing 50 to 100% by weight of a polyoxyethylene unit in the polyether moiety; image formation equipment equipped with the above elastic member; and a toner supply roller which is composed of a foamed elastic member mounted on a developing apparatus and which has a compression spring constant in the range of 0.25 to 5.0 N/mm and a surface friction resistance in the range of 0.4 to 1.2 N.
    Type: Grant
    Filed: November 6, 2001
    Date of Patent: November 16, 2004
    Assignee: Bridgestone Corporation
    Inventors: Junji Sakata, Hirotaka Yamazaki
  • Patent number: 6810227
    Abstract: A foamed elastic member according to the invention comprises an elastic member made of polyurethane foam molded by an in-mold foaming process, and has properly determined physical properties of its surface and/or properly determined shape and arrangement of foam cells opened on the surface. The foamed elastic member is suitably used for a toner feed roller in a developing device for electrically charging toner from a toner storage portion, feeding the toner onto the surface of a photosensitive member and forming a toner image corresponding to an electrostatic latent image on the surface of the photosensitive member. In this case, it exhibits an excellent toner scraping and toner feeding performance, to form an image free from such defect as irregularity in pitch and density, or free from reduction in density.
    Type: Grant
    Filed: November 26, 2002
    Date of Patent: October 26, 2004
    Assignee: Bridgestone Corporation
    Inventors: Junji Sakata, Hirotaka Yamazaki
  • Publication number: 20040167042
    Abstract: A lubricating oil for refrigerators which comprises a compound having oxygen as a base oil and is miscible with a refrigerant having no chlorine atoms and one carbon atom at a temperature of −10° C. or lower when the lubricating oil is comprised at least in one content within the range of 3 to 50% by weight based on the entire amount of a mixture comprising the lubricating oil and the refrigerant; and a hydraulic fluid composition for refrigerators which comprises a refrigerant having no chlorine atoms and one carbon atom and the lubricating oil described above. The hydraulic fluid composition exhibits excellent miscibility of the lubricating oil with the above refrigerant and, in particular, with difluoromethane and also exhibits excellent antiwear, lubricity and stability.
    Type: Application
    Filed: November 24, 2003
    Publication date: August 26, 2004
    Inventors: Hirotaka Yamazaki, Toshinori Tazaki, Naoko Tazaki, Kenji Mogami
  • Publication number: 20040157753
    Abstract: The present invention proposes a lubricating oil for refrigerators comprising, as the base oil, a polyester-based derivative or a polyvinyl ether derivative and a polycarbonate-based oxygenated compound; a polyoxyalkylene glycol derivative; or a polyester-based derivative or a polyvinyl ether derivative and a polyoxyalkylene glycol derivative. The lubricating oil exhibits excellent miscibility with a refrigerant having one carbon atom and no chlorine atoms and, in particular, with difluoromethane and provides a hydraulic fluid composition exhibiting excellent antiwear, lubricity and stability.
    Type: Application
    Filed: November 24, 2003
    Publication date: August 12, 2004
    Inventors: Toshinori Tazaki, Naoko Tazaki, Kenji Mogami, Hirotaka Yamazaki
  • Patent number: 6734151
    Abstract: A process for efficiently producing a high purity compound having oxygen which has a high volume specific resistance and a lubricating oil comprising the high purity compound having oxygen are provided. The process for producing a high purity compound having oxygen selected from a group consisting of high purity polyvinyl ether compounds, high purity polyalkylene glycol compounds, high purity polyol ester compounds, high purity cyclic polyether compounds and high purity carbonate compounds comprises a step of treating with an adsorbent at least one crude compound having oxygen selected from a group consisting of crude polyvinyl ether compounds, crude polyalkylene glycol compounds, crude polyol ester compounds, crude cyclic polyether compounds and crude carbonate compounds. The lubricating oil comprises the high purity compound having oxygen obtained in accordance with this process.
    Type: Grant
    Filed: March 11, 2002
    Date of Patent: May 11, 2004
    Assignees: Idemitsu Kosan Co., Ltd., Kyowa Yuka Co., Ltd.
    Inventors: Minoyuki Kubota, Kazuhiko Suzuki, Hirotaka Yamazaki, Tokuyuki Yoshimoto, Akihisa Ogawa, Shigeru Kamimori
  • Publication number: 20030147676
    Abstract: A foamed elastic member according to the invention comprises an elastic member made of polyurethane foam molded by an in-mold foaming process, and has properly determined physical properties of its surface and/or properly determined shape and arrangement of foam cells opened on the surface. The foamed elastic member is suitably used for a toner feed roller in a developing device for electrically charging toner from a toner storage portion, feeding the toner onto the surface of a photosensitive member and forming a toner image corresponding to an electrostatic latent image on the surface of the photosensitive member. In this case, it exhibits an excellent toner scraping and toner feeding performance, to form an image free from such defect as irregularity in pitch and density, or free from reduction in density.
    Type: Application
    Filed: November 26, 2002
    Publication date: August 7, 2003
    Applicant: BRIDGESTONE CORPORATION
    Inventors: Junji Sakata, Hirotaka Yamazaki
  • Patent number: 6572791
    Abstract: There is disclosed an elastic member constituted of polyurethane foam obtained by agitationally mixing with water, a urethane prepolymer synthesized from a polyol and a polyisocyanate, characterized by simultaneously employing as polyols, a (A) polymer polyol synthesized from a polyether polyol as a basis, comprising at least 70% by weight of oxypropylene moiety; and a (B) hydrophilic polyether polyol comprising at least 50% by weight of oxyethylene moiety, or simultaneously employing as polyols, the component (A), the component (B) and a (C) polyether polyol comprising at least 70% by weight of oxypropylene moiety. The above elastic member is simultaneously imparted with excellent characteristics such as low hardness, fine cells, low residual compressive strain, high strength and the like. The polyurethane foam which constitutes the elastic member can be produced by free foaming.
    Type: Grant
    Filed: December 7, 2000
    Date of Patent: June 3, 2003
    Assignee: Bridgestone Corporation
    Inventors: Junji Sakata, Hirotaka Yamazaki, Tadashi Nakajima, Takahiro Kawagoe
  • Patent number: 6480692
    Abstract: There are disclosed a toner supply roller which is composed of a foamed elastic body, and has a compression spring constant of 0.25 to 5.0 N/mm, and preferably has the number of cells per a length of 25 mm being 50 to 1200 in the foamed elastic layer; a developing apparatus which is equipped with the above toner supply roller and capable of affording images free from defect such as unevenness in pitch, density, etc.; another developing apparatus which is equipped with a toner supply roller and a developing roller, each being electroconductive, and which satisfies the requirement that the electric resistance of the toner supply roller is always lower than that of the developing roller at an impressed voltage of 100V to 500V, thereby enabling formation of satisfactory images by favorable electrification with the toner supply roller due to favorable adsorption of a toner onto the developing roller; and an image formation apparatus equipped with any of the above developing apparatuses.
    Type: Grant
    Filed: March 13, 2001
    Date of Patent: November 12, 2002
    Assignee: Bridgestone Corporation
    Inventors: Hirotaka Yamazaki, Junji Sakata
  • Publication number: 20020091170
    Abstract: There are disclosed an elastic member which comprises (A) polyurethane foam obtained by agitationally mixing a foaming agent, a foam stabiizer and a urethane prepolymer synthesized from a polyol and a polyisocyanate in the presence of a modified silicone, or (B) polyurethane foam obtained by agitationally mixing a polyol, a polyisocyanate, a modified silicone oil bearing a functional group reactive with a polyisocyanate, a foaming agent and a foam stabiizer comprising a polyether modified silicone containing 50 to 100% by weight of a polyoxyethylene unit in the polyether moiety; image formation equipment equipped with the above elastic member; and a toner supply roller which is composed of a foamed elastic member mounted on a developing apparatus and which has a compression spring constant in the range of 0.25 to 5.0 N/mm and a surface friction resistance in the range of 0.4 to 1.2 N.
    Type: Application
    Filed: November 6, 2001
    Publication date: July 11, 2002
    Applicant: Bridgestone Corporation
    Inventors: Junji Sakata, Hirotaka Yamazaki
  • Publication number: 20010036376
    Abstract: There are disclosed a toner supply roller which is composed of a foamed elastic body, and has a compression spring constant of 0.25 to 5.0 N/mm, and preferably has the number of cells per a length of 25 mm being 50 to 1200 in the foamed elastic layer; a developing apparatus which is equipped with the above toner supply roller and capable of affording images free from defect such as unevenness in pitch, density, etc.; another developing apparatus which is equipped with a toner supply roller and a developing roller, each being electroconductive, and which satisfies the requirement that the electric resistance of the toner supply roller is always lower than that of the developing roller at an impressed voltage of 100V to 500V, thereby enabling formation of satisfactory images by favorable electrification with the toner supply roller due to favorable adsorption of a toner onto the developing roller; and an image formation apparatus equipped with any of the above developing apparatuses.
    Type: Application
    Filed: March 13, 2001
    Publication date: November 1, 2001
    Applicant: Bridgestone Corporation
    Inventors: Hirotaka Yamazaki, Junji Sakata
  • Publication number: 20010003757
    Abstract: There is disclosed an elastic member constituted of polyurethane foam obtained by agitationally mixing with water, a urethane prepolymer synthesized from a polyol and a polyisocyanate, characterized by simultaneously employing as polyols, a (A) polymer polyol synthesized from a polyether polyol as a basis, comprising at least 70% by weight of oxypropylene moiety; and a (B) hydrophilic polyether polyol comprising at least 50% by weight of oxyethylene moiety, or simultaneously employing as polyols, the component (A), the component (B) and a (C) polyether polyol comprising at least 70% by weight of oxypropylene moiety. The above elastic member is simultaneously imparted with excellent characteristics such as low hardness, fine cells, low residual compressive strain, high strength and the like. The polyurethane foam which constitutes the elastic member can be produced by free foaming.
    Type: Application
    Filed: December 7, 2000
    Publication date: June 14, 2001
    Applicant: Bridgestone Corporation
    Inventors: Junji Sakata, Hirotaka Yamazaki, Tadashi Nakajima, Takahiro Kawagoe
  • Patent number: 5723214
    Abstract: A paper feed roll is formed of a rubber composition comprising (A) a composite material having a low molecular weight material retained in a medium material and (B) a rubber material. The low molecular weight material has a viscosity of up to 5.times.10.sup.5 centipoise at 100.degree. C. The difference in solubility parameter between the low molecular weight material and the medium material is up to 3.0. The weight ratio of the low molecular weight material to the medium material is at least 1.0. The difference in solubility parameter between the low molecular weight material and the rubber material is up to 4.0. A paper feed apparatus comprising the paper feed roll is also provided.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: March 3, 1998
    Assignee: Bridgestone Corporation
    Inventors: Hirotaka Yamazaki, Yasushi Imai, Shinichi Toyosawa, Yoshihide Fukahori
  • Patent number: 5376700
    Abstract: A rubber composition in which highly hard particles formed with a rubber-philic coating layer by a fluidized coating treatment are dispersed in a rubber material.
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: December 27, 1994
    Assignee: Bridgestone Corporation
    Inventors: Hirotaka Yamazaki, Yasunori Fukuta, Yoshihide Fukahori
  • Patent number: 5162395
    Abstract: A rubber composition which contains, in a matrix consisting mainly of rubber, irregularly shaped particles having high hardness, and subjected to surface treatment for improving their affinity for the matrix, or their adhesion to it.
    Type: Grant
    Filed: February 20, 1991
    Date of Patent: November 10, 1992
    Assignee: Bridgestone Corporation
    Inventors: Hirotaka Yamazaki, Yasunori Fukuta, Yoshihide Fukahori