Patents by Inventor Norihito Shida

Norihito Shida 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: 20120251760
    Abstract: A method for producing a glass substrate for a magnetic disk involving the use of a polishing pad having: a first resin foam layer which forms the polishing surface, includes a resin foam having pores with a pore diameter of more than 20 ?m and has a thickness of 400 ?m or less; and a second resin foam layer which is provided between a platen for fixing the polishing pad and the first resin foam layer, includes a resin foam having pores with a pore diameter of 20 ?m or less and has a thickness of 50 to 250 ?m, and in which a total thickness of the first resin foam layer and the second resin foam layer is 550 ?m or less, and a international rubber hardness degree of the polishing pad measured by the M method according to JIS K6253 is 40 IRHD or more.
    Type: Application
    Filed: September 26, 2011
    Publication date: October 4, 2012
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Mizuho ISHIDA, Norihito Shida, Katsuhiro Matsumoto, Kazuo Mannami
  • Patent number: 8092280
    Abstract: The present invention relates to a method for producing a glass substrate for a magnetic disk, the method including a step of polishing a main surface of a circular glass plate while supplying a polishing slurry containing a polishing material, in which polishing is performed, after a polishing surface is subjected to dressing treatment, by using a polishing pad having: a first resin foam layer which forms the polishing surface, includes a resin foam having pores with a pore diameter of more than 20 ?m and has a thickness of 400 ?m or less; and a second resin foam layer which is provided between a platen for fixing the polishing pad and the first resin foam layer, includes a resin foam having pores with a pore diameter of 20 ?m or less and has a thickness of 50 to 250 ?m, and in which a total thickness of the first resin foam layer and the second resin foam layer is 550 ?m or less, and a international rubber hardness degree of the polishing pad measured by the M method according to JIS K6253 is 40 IRHD or mor
    Type: Grant
    Filed: December 1, 2009
    Date of Patent: January 10, 2012
    Assignee: Asahi Glass Company, Limited
    Inventors: Mizuho Ishida, Norihito Shida, Katsuhiro Matsumoto, Kazuo Mannami
  • Publication number: 20110189506
    Abstract: The present invention relates to a glass substrate for a magnetic recording medium, which is a disk-shaped glass substrate for a magnetic recording medium having a circular hole at the center thereof, in which the glass substrate for a magnetic recording medium has an inner peripheral side surface, an outer peripheral side surface and both main surfaces, and the both main surfaces have parallelism of 3.2 ?m or less in at least a recording and reproducing region thereof.
    Type: Application
    Filed: January 31, 2011
    Publication date: August 4, 2011
    Applicant: Asahi Glass Company, Limited
    Inventors: Kazuo Mannami, Hitoshi Mishiro, Norihito Shida, Masabumi Ito, Hiroyuki Masuda, Toru Momose
  • Publication number: 20100136372
    Abstract: The present invention relates to a method for producing a glass substrate for a magnetic disk, the method including a step of polishing a main surface of a circular glass plate while supplying a polishing slurry containing a polishing material, in which polishing is performed, after a polishing surface is subjected to dressing treatment, by using a polishing pad having: a first resin foam layer which forms the polishing surface, includes a resin foam having pores with a pore diameter of more than 20 ?m and has a thickness of 400 ?m or less; and a second resin foam layer which is provided between a platen for fixing the polishing pad and the first resin foam layer, includes a resin foam having pores with a pore diameter of 20 ?m or less and has a thickness of 50 to 250 ?m, and in which a total thickness of the first resin foam layer and the second resin foam layer is 550 ?m or less, and a international rubber hardness degree of the polishing pad measured by the M method according to JIS K6253 is 40 IRHD or mor
    Type: Application
    Filed: December 1, 2009
    Publication date: June 3, 2010
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Mizuho ISHIDA, Norihito Shida, Katsuhiro Matsumoto, Kazuo Mannami