Patents by Inventor Kenta Iwasawa

Kenta Iwasawa 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: 8232219
    Abstract: The present invention relates to a dielectric ceramic composition comprises a main component including a dielectric oxide having a composition shown by [(Ca1-xSrx)O]m[(Zr1-y-z-?TiyHf2Mn?)O2], note that, 0.991?m?1.010, 0?x?1, 0?y?0.1, 0<z?0.02, 0.002<??0.05), 0.1 to 0.5 parts by mol of Al2O3 and 0.5 to 5.0 parts by mol of SiO2 with respect to 100 parts by mol of the main component. A purpose of the present invention is to provide a dielectric ceramic composition available to prevent the occurrence of crack even when a dielectric layer is made thin, for example, 2 ?m or less, while maintaining various advantageous properties of a dielectric ceramic composition of [(CaSr)O]m[(TiZrHf)O2] type.
    Type: Grant
    Filed: March 20, 2009
    Date of Patent: July 31, 2012
    Assignee: TDK Corporation
    Inventors: Tomoaki Nonaka, Tetsuo Takaishi, Kenta Iwasawa, Hiroshi Sasaki
  • Patent number: 7820578
    Abstract: The object of the present invention is to provide a method of production of dielectric ceramic composition which can lower the firing temperature without compensating the dielectric characteristics. The method of production according to the present invention is characterized by comprising steps of; preparing a dielectric oxide expressed by composition formula of [(CaxSr1-x)O]m[(TiyZr1-y-zHfz)O2] (x, y, z, and m in the formula are; 0.5?x?1.0, 0.01?y?0.10, 0<z?0.20 and 0.90?m?1.04 respectively), mixing, with respect to 100 parts by weight of the dielectric ceramic composition, 1 to 10 parts by weight of a sintering aid and 0.1 to 1.5 parts by weight of sodium oxide, sodium carbonate or a mixture thereof in terms of Na2O, and firing an obtained mixture; wherein said sintering aid comprises, with respect to 100 wt % of said sintering aid, 30 to 69 wt % of manganese compound in terms of MnO, 1 to 20 wt % of aluminum oxide in terms of Al2O3, and 30 to 50 wt % of silicon oxide in terms of SiO2.
    Type: Grant
    Filed: November 7, 2008
    Date of Patent: October 26, 2010
    Assignee: TDK Corporation
    Inventors: Tetsuo Takaishi, Tomoaki Nonaka, Hiroshi Sasaki, Tsutomu Odashima, Kenta Iwasawa
  • Publication number: 20090246541
    Abstract: The present invention relates to a dielectric ceramic composition comprises a main component including a dielectric oxide having a composition shown by [(Ca1-xSrx)O]m[(Zr1-y-z-?TiyHf2Mn?)O2], note that, 0.991?m?1.010, 0?x?1, 0?y?0.1, 0<z?0.02, 0.002<??0.05), 0.1 to 0.5 parts by mol of Al2O3 and 0.5 to 5.0 parts by mol of SiO2 with respect to 100 parts by mol of the main component. A purpose of the present invention is to provide a dielectric ceramic composition available to prevent the occurrence of crack even when a dielectric layer is made thin, for example, 2 ?m or less, while maintaining various advantageous properties of a dielectric ceramic composition of [(CaSr)O]m[(TiZrHf)O2] type.
    Type: Application
    Filed: March 20, 2009
    Publication date: October 1, 2009
    Applicant: TDK CORPORATION
    Inventors: Tomoaki Nonaka, Tetsuo Takaishi, Kenta Iwasawa, Hiroshi Sasaki
  • Publication number: 20090137381
    Abstract: The object of the present invention is to provide a method of production of dielectric ceramic composition which can lower the firing temperature without compensating the dielectric characteristics. The method of production according to the present invention is characterized by comprising steps of; preparing a dielectric oxide expressed by composition formula of [(CaxSr1-x)O]m[(TiyZr1-y-zHfz)O2] (x, y, z, and m in the formula are; 0.5?x?1.0, 0.01?y?0.10<z?0.20 and 0.90?m?1.04 respectively), mixing, with respect to 100 parts by weight of the dielectric ceramic composition, 1 to 10 parts by weight of a sintering aid and 0.1 to 1.5 parts by weight of sodium oxide, sodium carbonate or a mixture thereof in terms of Na2O, and firing an obtained mixture; wherein said sintering aid comprises, with respect to 100 wt % of said sintering aid, 30 to 69 wt % of manganese compound in terms of MnO, 1 to 20 wt % of aluminum oxide in terms of Al2O3, and 30 to 50 wt % of silicon oxide in terms of SiO2.
    Type: Application
    Filed: November 7, 2008
    Publication date: May 28, 2009
    Applicant: TDK CORPORATION
    Inventors: Tetsuo Takaishi, Tomoaki Nonaka, Hiroshi Sasaki, Tsutomu Odashima, Kenta Iwasawa