Patents by Inventor Takehiro Hiuga

Takehiro Hiuga 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).

  • Dielectric ceramic and process of preparing it
    Patent number: 4897374
    Abstract: A dielectric ceramic having the composition represented by the general formula (I):Ba.sub.x A.sub.y B.sub.1-x-y F.sub.z O.sub.wwherein A is at least one selected from the group consisting of Mg, Zn, Ni and Co; B is at least one selected from Ta and Nb; x, y, and z are numbers represented by 0.48.ltoreq.x.ltoreq.0.52, 0.15.ltoreq.y.ltoreq.0.19 and 0.00025.ltoreq.z.ltoreq.0.05, respectively; and w is a number such that the total electric charges of cations of A and B and anions of F are neutralized to make the ceramic substantially neutral as a whole, and a process of preparing the dielectric ceramic. This ceramic has a high dielectric constant and unloaded Q and has a small temperature coefficient of resonance frequency.
    Type: Grant
    Filed: December 15, 1988
    Date of Patent: January 30, 1990
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Kazutoshi Matsumoto, Ko Takada, Takehiro Hiuga, Tetsuya Mukai