Patents by Inventor Takumi Koshimizu

Takumi Koshimizu 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).

  • Method for producing glass substrate for magnetic disk and method for manufacturing magnetic disk
    Patent number: 9038417
    Abstract: When mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.
    Type: Grant
    Filed: May 12, 2014
    Date of Patent: May 26, 2015
    Assignee: HOYA CORPORATION
    Inventors: Toshio Takizawa, Takumi Koshimizu, Yoshinori Marumo, Masahiro Katagiri
  • METHOD FOR PRODUCING GLASS SUBSTRATE FOR MAGNETIC DISK AND METHOD FOR MANUFACTURING MAGNETIC DISK
    Publication number: 20140248424
    Abstract: When mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.
    Type: Application
    Filed: May 12, 2014
    Publication date: September 4, 2014
    Applicant: HOYA CORPORATION
    Inventors: Toshio TAKIZAWA, Takumi KOSHIMIZU, Yoshinori MARUMO, Masahiro KATAGIRI
  • Method for producing glass substrate for magnetic disk and method for manufacturing magnetic disk
    Patent number: 8763428
    Abstract: When mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: July 1, 2014
    Assignee: Hoya Corporation
    Inventors: Toshio Takizawa, Takumi Koshimizu, Yoshinori Marumo, Masahiro Katagiri
  • Method For Producing Glass Substrate For Magnetic Disk And Method For Manufacturing Magnetic Disk
    Publication number: 20090158775
    Abstract: When mirror polishing is performed on a glass substrate by bringing a polishing pad into contact with the surface of the glass substrate while supplying a polishing liquid containing polishing grains to the substrate surface, the pH of the polishing liquid is maintained within a certain range or the agglomeration degree or dispersion degree of the polishing liquid is controlled. Consequently, an adequate mirror polishing rate can be maintained and there can be obtained a glass substrate having a good end shape.
    Type: Application
    Filed: March 16, 2007
    Publication date: June 25, 2009
    Applicant: HOYA CORPORATION
    Inventors: Toshio Takizawa, Takumi Koshimizu, Yoshinori Marumo, Masahiro Katagiri