Patents by Inventor Hiroshi Ojima

Hiroshi Ojima 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: 5650367
    Abstract: A dielectric ceramic composition containing, per 100 parts by weight of BaTiO.sub.3, at least either one of Nb.sub.2 O.sub.5 or Ta.sub.2 O.sub.5 in an amount of from 0.8 to 3.5 parts by weight, MgO in an amount of from 0.06 to 0.7 parts by weight, oxides of rare earth elements in an amount of from 0.005 to 0.520 parts by weight, and MnO in an amount of from 0.01 to 0.30 parts by weight in the form of MnCO.sub.3, the molar ratio of MgO to either Nb.sub.2 O.sub.5 or Ta.sub.2 O.sub.5 being from 0.5 to 2.2. The dielectric ceramic composition has a dielectric constant of not smaller than 2500, is fired at a temperature of not higher than 1300.degree. C., exhibits a change of capacitance depending upon the temperature satisfying X7R of the IEA Standards, a dielectric loss of not larger than 2.5%, a small voltage dependence, and an insulation resistance of not smaller than 10.sup.4 M.OMEGA., and is suited as a material for producing ceramic capacitors and resonators.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: July 22, 1997
    Assignee: Kyocera Corporation
    Inventors: Nobuyoshi Fujikawa, Yoshihiro Fujioka, Yasushi Yamakuchi, Shin-ichi Osawa, Hiroshi Ojima