Patents by Inventor Hirohisa Ishizaki

Hirohisa Ishizaki 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: 11908601
    Abstract: There is provided a magnetic responsiveness composite material capable of increasing viscosity by applying a magnetic field when compounded together with a liquid in a composition. The magnetic responsive composite material comprises first particles as core particles composed of a nonmagnetic inorganic material and second particles composed of a magnetic material adhering to at least a part of surfaces of the first particles. A lipophilic treatment agent is applied to at least a part of surfaces of the second particles. The second particles satisfy a relationship of having a smaller average particle diameter than that of the first particles. A lipophilic treatment agent is preferably at least one kind selected from coupling agents and surfactants.
    Type: Grant
    Filed: April 13, 2021
    Date of Patent: February 20, 2024
    Assignee: SOMAR CORPORATION
    Inventors: Hirohisa Ishizaki, Akira Ochiai
  • Patent number: 11578183
    Abstract: A resin composition including: a magnetic fluid that includes magnetic particles, a dispersant, and a dispersion medium; and a resin or precursor thereof that includes, in a molecule thereof, at least one partial structure selected from the group consisting of a diene skeleton, a silicone skeleton, a urethane skeleton, a 4- to 7-membered ring lactone skeleton, an alkyl group having from 6 to 30 carbon atoms and an alkylene group having from 6 to 30 carbon atoms, a production method thereof, a resin composition molded body obtained by using the resin composition, and a production method thereof.
    Type: Grant
    Filed: November 27, 2017
    Date of Patent: February 14, 2023
    Assignee: SOMAR CORPORATION
    Inventors: Hirohisa Ishizaki, Akira Ochiai
  • Patent number: 11407159
    Abstract: The present invention is a method that enables continuous injection molding of a thermosetting resin composition and reuse of an unnecessary part produced during the molding. The method includes injecting a thermosetting resin composition into a mold while a curing reaction of the resin composition is incomplete. The thermosetting resin composition is then cooled in the mold until becoming semi-cured and removed as a semi-cured product from the mold. The semi-cured product is separated from the unnecessary part and separately heated to progress a thermosetting reaction of the thermosetting resin composition. The unnecessary part may be used as a reworked raw material by regrinding the unnecessary part and mixing it with a fresh thermosetting resin composition. Then, a resultant mixture is used to perform a new injection molding.
    Type: Grant
    Filed: April 18, 2016
    Date of Patent: August 9, 2022
    Assignee: SOMAR CORPORATION
    Inventors: Hirohisa Ishizaki, Akira Ochiai
  • Publication number: 20210327622
    Abstract: There is provided a magnetic responsiveness composite material capable of increasing viscosity by applying a magnetic field when compounded together with a liquid in a composition. The magnetic responsive composite material comprises first particles as core particles composed of a nonmagnetic inorganic material and second particles composed of a magnetic material adhering to at least a part of surfaces of the first particles. A lipophilic treatment agent is applied to at least a part of surfaces of the second particles. The second particles satisfy a relationship of having a smaller average particle diameter than that of the first particles. A lipophilic treatment agent is preferably at least one kind selected from coupling agents and surfactants.
    Type: Application
    Filed: April 13, 2021
    Publication date: October 21, 2021
    Inventors: Hirohisa Ishizaki, Akira Ochiai
  • Patent number: 11004582
    Abstract: A magnetic powder is obtained by removing a dispersion medium from a magnetic fluid that includes magnetic particles, a dispersant and the dispersion medium. A magnetic powder composition includes the magnetic powder and a resin material, and a magnetic powder composition molded body is obtained therefrom. A method of producing a magnetic powder includes removing a dispersion medium from a magnetic fluid containing magnetic particles, a dispersant and the dispersion medium, and powdering a solid component obtained by removing the dispersion medium. A method of producing a magnetic powder composition and a method of producing a magnetic powder composition molded product are also provided.
    Type: Grant
    Filed: July 17, 2014
    Date of Patent: May 11, 2021
    Assignee: SOMAR CORPORATION
    Inventors: Hirohisa Ishizaki, Akira Ochiai
  • Publication number: 20200312504
    Abstract: A magnetorheological fluid composition with excellent dispersion stability of magnetic particles and fluidity is provided. The magnetorheological fluid composition comprises magnetic particles, a dispersion medium, a viscosity modifier and hollow particles. The hollow particles preferably have an average primary particle diameter of 5 to 500 nm. The hollow particles are preferably at least one kind selected from a group consisting of carbon particles, silica and crosslinked styrene-acryl. The viscosity modifier is preferably at least one kind selected from a group consisting of castor oil, fatty acid amides, polyolefins and (meth)acrylate esters.
    Type: Application
    Filed: March 20, 2020
    Publication date: October 1, 2020
    Inventors: Hirohisa Ishizaki, Akira Ochiai
  • Patent number: 10663065
    Abstract: An embodiment of the present invention provides a sealing member including a magnetic powder and at least one selected from the group consisting of a rubber material and a resin material, the magnetic powder being obtained by removing a dispersion medium from a magnetic fluid including magnetic particles, a dispersant and dispersion medium.
    Type: Grant
    Filed: December 22, 2015
    Date of Patent: May 26, 2020
    Assignee: SOMAR CORPORATION
    Inventors: Hirohisa Ishizaki, Akira Ochiai
  • Publication number: 20190309143
    Abstract: A resin composition including: a magnetic fluid that includes magnetic particles, a dispersant, and a dispersion medium; and a resin or precursor thereof that includes, in a molecule thereof, at least one partial structure selected from the group consisting of a diene skeleton, a silicone skeleton, a urethane skeleton, a 4- to 7-membered ring lactone skeleton, an alkyl group having from 6 to 30 carbon atoms and an alkylene group having from 6 to 30 carbon atoms, a production method thereof, a resin composition molded body obtained by using the resin composition, and a production method thereof.
    Type: Application
    Filed: November 27, 2017
    Publication date: October 10, 2019
    Inventors: Hirohisa ISHIZAKI, Akira OCHIAI
  • Publication number: 20180099445
    Abstract: The present invention is a method that enables continuous injection molding of a thermosetting resin composition and reuse of an unnecessary part produced during the molding. The method includes injecting a thermosetting resin composition into a mold while a curing reaction of the resin composition is incomplete. The thermosetting resin composition is then cooled in the mold until becoming semi-cured and removed as a semi-cured product from the mold. The semi-cured product is separated from the unnecessary part and separately heated to progress a thermosetting reaction of the thermosetting resin composition. The unnecessary part may be used as a reworked raw material by regrinding the unnecessary part and mixing it with a fresh thermosetting resin composition. Then, a resultant mixture is used to perform a new injection molding.
    Type: Application
    Filed: April 18, 2016
    Publication date: April 12, 2018
    Applicant: SOMAR CORPORATION
    Inventors: Hirohisa ISHIZAKI, Akira OCHIAI
  • Publication number: 20170356551
    Abstract: An embodiment of the present invention provides a sealing member including a magnetic powder and at least one selected from the group consisting of a rubber material and a resin material, the magnetic powder being obtained by removing a dispersion medium from a magnetic fluid including magnetic particles, a dispersant and dispersion medium.
    Type: Application
    Filed: December 22, 2015
    Publication date: December 14, 2017
    Inventors: Hirohisa ISHIZAKI, Akira OCHIAI
  • Publication number: 20160163437
    Abstract: A magnetic powder is obtained by removing a dispersion medium from a magnetic fluid that includes magnetic particles, a dispersant and the dispersion medium. A magnetic powder composition includes the magnetic powder and a resin material, and a magnetic powder composition molded body is obtained therefrom. A method of producing a magnetic powder includes removing a dispersion medium from a magnetic fluid containing magnetic particles, a dispersant and the dispersion medium, and powdering a solid component obtained by removing the dispersion medium. A method of producing a magnetic powder composition and a method of producing a magnetic powder composition molded product are also provided.
    Type: Application
    Filed: July 17, 2014
    Publication date: June 9, 2016
    Inventors: Hirohisa ISHIZAKI, Akira OCHIAI
  • Patent number: 6290233
    Abstract: A sealing apparatus which is disposed between the media side and the bearing side and adapted to hermetically seal members rotating concentrically relative to each other, wherein a passageway having in a U-shaped cross section is formed by an outer shielding member on the media side, an outer shielding member on the bearing side and an inner shielding member, the end portion of which is inserted into the cavity between the outer shielding members. The end portion of the inner shielding member has a T-shape or L-shape. A magnet is arranged at either the inner shielding member or the outer shielding member. A ferrofluid is retained in the cavity by the surrounding magnet. An oil repellent material may be coated on the surface of the inner shielding member except for a portion extending into the cavity and an adhered portion on its inner diameter side.
    Type: Grant
    Filed: September 17, 1999
    Date of Patent: September 18, 2001
    Inventors: Akira Yamamura, Hirohisa Ishizaki, Heiichi Unozawa
  • Patent number: 5876037
    Abstract: A magnetic fluid sealing device for preventing magnetic fluid from flowing out or spattering under the influence of rotation of a rotatable shaft, thereby preventing contamination of the surroundings. The device includes a pole piece 1 formed with a step portion 13 whose front end surface 4 is disposed more inwardly than the proximal end surface, and the surface of the step portion 13 opposed to a magnetic body 6 serves as a barrier wall 10. Thereby, magnetic fluid 7 is prevented from flowing out or spattering into the surroundings.
    Type: Grant
    Filed: November 19, 1996
    Date of Patent: March 2, 1999
    Assignee: Ferrotec Corporation
    Inventors: Hirohisa Ishizaki, Sirou Tsuda