Patents by Inventor Shu Ishiguro

Shu Ishiguro 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).

  • Magnetic recording medium
    Patent number: 4835049
    Abstract: The invention relate to a magnetic recording medium which comprises a magnetic layer on a support. The magnetic layer contains an iron-aluminum alloy magnetic powder and a carbon black having a BET specific surface area of from 15 to 80 m.sup.2 /g and a DBP oil absorption of the carbon black from 110 to 200 ml/100 g.
    Type: Grant
    Filed: December 29, 1987
    Date of Patent: May 30, 1989
    Assignee: Konica Corporation
    Inventors: Shu Ishiguro, Ryosuke Isobe
  • Highly running-endurant magnetic recording medium
    Patent number: 4818606
    Abstract: A magnetic recording medium comprising a nonmagnetic support having thereon a magnetic recording layer comprising a magnetic layer containing ferromagnetic metal powder wherein the magnetic metal powder has a BET specific surface area of not less than 40 m.sup.2 /g and the magnetic recording layer contains a fatty acid having a neutralization value of not more than 250, an ester of fatty acid and a carbon black having a DBP oil absorption of not less than 110 ml/100 g and an average particle size of not more than 60 m.mu.. The magnetic recording medium is improved on the electromagnetic conversion property as well as on the running endurance.
    Type: Grant
    Filed: December 2, 1987
    Date of Patent: April 4, 1989
    Assignee: Konica Corporation
    Inventors: Noboru Koyama, Shu Ishiguro, Ryosuke Isobe