Patents by Inventor Haruo Ando

Haruo Ando 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: 4741953
    Abstract: A magnetic recording medium having a broad dynamic range over an entire range of frequency which comprises a substrate material and a magnetic layer comprising magnetic particles and a resinous binder provided on at least one of the surfaces of the substrate material, characterized in that the magnetic layer is constructed as a double layered structure comprising an upper layer and a lower layer and which satisfies the following requirements:H.sub.1 >H.sub.2 (1)r.sub.1 <r.sub.2 (2)wherein H.sub.1 is the coercive force of the upper layer, H.sub.2 is the coercive force of the lower layer, r.sub.1 is the average size of the long axis of magnetic particles in the upper layer and r.sub.2 is the average size of the long axis of magnetic particles in the lower layer, and the lower layer comprises as the magnetic particles iron oxide magnetic particles having a particle void content of not more than 5% by volume in average.
    Type: Grant
    Filed: March 20, 1986
    Date of Patent: May 3, 1988
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Yoshiharu Katsuta, Haruo Ando