Patents by Inventor Koo Honjoo

Koo Honjoo 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).

  • Coil impregnant of epoxy resin from polyhydric phenol mixture
    Patent number: 5656350
    Abstract: A thermosetting resin composition comprising:[A] a polyfunctional epoxy resin produced from a reaction between a mixture of at least two polyhydric phenols selected from (a) bis(4-hydroxyphenyl)methane, (b) bis(4-hydroxyphenyl)ethane, (c) bis(4-hydroxyphenyl)-propane, (d) tris(4-hydroxyphenyl)alkane and (e) tetra(4-hydroxyphenyl)alkane, and epichlorohydrin, and[B] an acid anhydride curing agent; and a coil and a panel formed of said composition.
    Type: Grant
    Filed: January 31, 1995
    Date of Patent: August 12, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Toru Koyama, Chikashi Kanno, Hirokazu Takasaki, Koo Honjoo, Shinichi Toyoda, Hiroshi Suzuki, Ikushi Kano
  • Magnetic recording medium
    Patent number: 4828924
    Abstract: A magnetic recording medium of high durability comprising a substrate material and a magnetic layer provided on at least one surface of the substrate material, the magnetic layer comprising magnetic powder and a resinous binder, characterized in that the magnetic layer comprises further at least one compound of the formula:Rf--CH.sub.2 --R).sub.m X (I)wherein Rf is a fluorinated polyoxyalkyl group having 8 to 152 carbon atoms, R is an oxyalkylene group having 2 or 3 carbon atoms, X is a polar group such as --OH, --OCH.sub.3, -O-lower alkylene-COOH or -O-CO-lower alkylene-OH and m is an integer of not less than 1 uniformly and entirely dispersed in the magnetic layer.
    Type: Grant
    Filed: October 30, 1987
    Date of Patent: May 9, 1989
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Mitsutoshi Shoji, Koo Honjoo, Yoshiharu Honma, Fumio Nakano, Toshikazu Narahara