Patents by Inventor Tadanori Nagao

Tadanori Nagao 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).

  • Polishing composition and method
    Patent number: 6607571
    Abstract: To provide a polishing composition which enables maintenance of excellent properties and high quality of the surface of a hard disk without lowering polishing rate during polishing of the surface, and which can provide a polished surface in which the amount of dub-off is considerably reduced as compared with that of a conventional level, a polishing composition containing water, a polishing material (particularly alumina), a polishing accelerator, and at least one of hydroxypropyl cellulose and hydroxyalkyl alkyl cellulose is provided.
    Type: Grant
    Filed: August 21, 2002
    Date of Patent: August 19, 2003
    Assignees: Showa Denko K.K., Yamaguchi Seiken Kogyo K.K.
    Inventors: Ken Ishitobi, Masahiro Nozaki, Tadanori Nagao, Yoshiki Hayashi
  • Polishing composition and method
    Publication number: 20030029095
    Abstract: To provide a polishing composition which enables maintenance of excellent properties and high quality of the surface of a hard disk without lowering polishing rate during polishing of the surface, and which can provide a polished surface in which the amount of dub-off is considerably reduced as compared with that of a conventional level, a polishing composition containing water, a polishing material (particularly alumina), a polishing accelerator, and at least one of hydroxypropyl cellulose and hydroxyalkyl alkyl cellulose is provided.
    Type: Application
    Filed: August 21, 2002
    Publication date: February 13, 2003
    Applicant: SHOWA DENKO K.K.
    Inventors: Ken Ishitobi, Masahiro Nozaki, Tadanori Nagao, Yoshiki Hayashi
  • Polishing composition and method
    Patent number: 6488729
    Abstract: To provide a polishing composition which enables maintenance of excellent properties and high quality of the surface of a hard disk without lowering polishing rate during polishing of the surface, and which can provide a polished surface in which the amount of dub-off is considerably reduced as compared with that of a conventional level, a polishing composition containing water, a polishing material (particularly alumina), a polishing accelerator, and at least one of hydroxypropyl cellulose and hydroxyalkyl alkyl cellulose is provided.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: December 3, 2002
    Assignees: Showa Denko K.K., Yamaguchi Seiken Kogyo K.K.
    Inventors: Ken Ishitobi, Masahiro Nozaki, Tadanori Nagao, Yoshiki Hayashi