Patents by Inventor Osamu Iizawa

Osamu Iizawa 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).

  • High dielectric constant type ceramic composition consisting essentially of Pb(Fe.sub.1/2 Nb.sub.1/2)O.sub.3 -Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 -Pb(Mg.sub.1/2 W.sub.1/2)O.sub.3
    Patent number: 4287075
    Abstract: A novel ceramic composition exhibiting a solid solution structure of Pb(Fe.sub.1/2 Nb.sub.1/2)O.sub.3 -Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 -Pb(Mg.sub.1/2 W.sub.1/2)O.sub.3, can be sintered at a low sintering temperature; have a high insulation resistance; have a relatively high dielectric constant in the high dielectric type ceramic dielectrics, and; have a low dielectric loss.A particular amount of the additives, i.e., Pb-(Mn.sub.2/3 W.sub.1/3)O.sub.3, Pb(Mb.sub.1/2 W.sub.1/2)O.sub.3 Pb(Mn.sub.1/2 Nb.sub.2/3)O.sub.3, MnO, Pb(Mn.sub.1/3 Ta.sub.2/3)O.sub.3, Li.sub.2 O, Cr.sub.2 O.sub.3 and CeO.sub.2, is added into the composition mentioned above.
    Type: Grant
    Filed: April 16, 1979
    Date of Patent: September 1, 1981
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Shinobu Fujiwara, Kiyoshi Furukawa, Nobuaki Kikuchi, Osamu Iizawa, Hitoshi Tanaka, Hisayoshi Ueoka
  • High dielectric constant type ceramic composition
    Patent number: 4265668
    Abstract: A basic ceramic composition of high dielectric constant type ceramic composition comprises from 68.67 to 69.19% of PbO, from 3.67 to 4.09% of MgO, from 24.17 to 26.99% of Nb.sub.2 O.sub.5 and from 0.25 to 2.97% of TiO.sub.2, all percentages being by weight. Modified composition may comprise additive of Pb(Mn.sub.2/3 W.sub.1/3)O.sub.3, Pb(Mn.sub.1/3 Nb.sub.2/3)O.sub.3, Pb(Mn.sub.1/3 Ta.sub.2/3)O.sub.3, Pb(Mn.sub.1/2 W.sub.1/2)O.sub.3, MnO, and MgO. Modified composition may comprise Ba, Sr and Ca, which replace Pb of the basic ceramic composition. In a modified composition, the content of B site elements may be larger than that of A site element of an ABO.sub.3 crystal of the high dielectric constant type ceramic composition. A high dielectric constant, low dielectric loss, low temperature dependence of capacitance, high insulation resistance and a low sintering temperature are provided by the ceramic compositions of the present invention.
    Type: Grant
    Filed: October 29, 1979
    Date of Patent: May 5, 1981
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Shinobu Fujiwara, Kiyoshi Furukawa, Nobuaki Kikuchi, Osamu Iizawa, Hitoshi Tanaka
  • High dielectric constant type ceramic composition
    Patent number: 4235635
    Abstract: A novel ceramic composition exhibiting a solid solution structure of Pb(Fe.sub.2/3 W.sub.1/3)O.sub.3 --Pb(ZrO.sub.3), can be sintered at a low sintering temperature; have a high insulation resistance; have a relatively high dielectric constant in the high dielectric type ceramic dielectrics; have a low dependence of dielectric constant upon temperature, and; have a low dielectric loss.A particular amount of the additives, i.e., MnO, Pb(Mn.sub.1/3 Nb.sub.2/3)O.sub.3, Pb(Mn.sub.1/2 W.sub.1/2)O.sub.3, Pb(Mn.sub.2/3 W.sub.1/3)O.sub.3, Pb(Mn.sub.1/3 Ta.sub.2/3)O.sub.3, Cr.sub.2 O.sub.3 and CeO.sub.2, is added into the composition mentioned above.
    Type: Grant
    Filed: July 26, 1979
    Date of Patent: November 25, 1980
    Assignee: TDK Electronics Co., Inc.
    Inventors: Osamu Iizawa, Shinobu Fujiwara, Hisayoshi Ueoka, Kiyoshi Furukawa, Nobuaki Kikuchi, Hitoshi Tanaka
  • High dielectric constant type ceramic composition consisting essentially of Pb(Fe.sub.1/2 Nb.sub.1/2)O.sub.3 -Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3
    Patent number: 4216102
    Abstract: A novel ceramic composition exhibiting a solid solution structure of Pb(Fe.sub.1/2 Nb.sub.1/2)O.sub.3 --Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3, can be sintered at a low sintering temperature; have a high insulation resistance; have a relatively high dielectric constant in the high dielectric type ceramic dielectrics, and; have a low dielectric loss.A particular amount of the additives, i.e., pb(Mn.sub.1/2 W.sub.1/2)O.sub.3, Pb(Mn.sub.1/3 Nb.sub.2/3)O.sub.3, MnO, Pb(Mn.sub.1/3 Ta.sub.2/3)O.sub.3 Li.sub.2 O, Cr.sub.2 O.sub.3 and CeO.sub.2, is added into the composition mentioned above.
    Type: Grant
    Filed: April 6, 1979
    Date of Patent: August 5, 1980
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Kiyoshi Furukawa, Shinobu Fujiwara, Nobuaki Kikuchi, Osamu Iizawa, Hitoshi Tanaka, Hisayoshi Ueoka
  • High dielectric constant type ceramic composition consisting essentially of Pb(Fe.sub.1/2 Nb.sub.1/2)O.sub.3 -Pb(Mg.sub.1/3 Ta.sub.2/3)O.sub.3
    Patent number: 4216103
    Abstract: A novel ceramic composition exhibiting a solid solution structure of Pb(Fe.sub.1/2 Nb.sub.178 )O.sub.3 -Pb(Mg.sub.1/3 Ta.sub.2/3)O.sub.3, can be sintered at a low sintering temperature; have a high insulation resistance; have a relatively high dielectric constant in the high dielectric type ceramic dielectrics, and; have a low dielectric loss.A particular amount of the additives, i.e., Pb(Mn.sub.1/2 W.sub.1/2)O.sub.3, Pb(Mn.sub.1/3 Nb.sub.170 )O.sub.3, MnO, Pb(Mn.sub.1/3 Ta.sub.170 )O.sub.3, Li.sub.2 O, Cr.sub.2 O.sub.3 and CeO.sub.2, is added into the composition mentioned above.
    Type: Grant
    Filed: April 6, 1979
    Date of Patent: August 5, 1980
    Assignee: TDK Electronics Co., Ltd.
    Inventors: Shinobu Fujiwara, Kiyoshi Furukawa, Nobuaki Kikuchi, Osamu Iizawa, Hitoshi Tanaka, Hisayoshi Ueoka