Patents by Inventor Taku Masai

Taku Masai 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: 10710932
    Abstract: The object of the present invention is to provide the dielectric composition having good specific permittivity, high DC breakdown voltage and AC breakdown voltage, small dielectric loss and heat generating property, and good temperature property even though lead is not substantially used. A dielectric composition of the first aspect includes a, Ca, Bi, Ti, and Sr, wherein the dielectric composition includes two phases having different Sr characteristic X ray intensities when a characteristic X ray intensity derived from Sr is measured by EPMA, and when Sr1 represents the characteristic X ray intensity derived from Sr of a first phase measured by EPMA and Sr2 represents the characteristic X ray intensity derived from Sr of a second phase measured by EPMA, a ratio (Sr2/Sr1) of Sr2 with respect to Sr1 satisfies 2 or larger.
    Type: Grant
    Filed: March 19, 2019
    Date of Patent: July 14, 2020
    Assignee: TDK CORPORATION
    Inventors: Daisuke Ohtsu, Taku Masai, Liu Hailong, Liang Liping
  • Publication number: 20190300436
    Abstract: The object of the present invention is to provide the dielectric composition having good specific permittivity, high DC breakdown voltage and AC breakdown voltage, small dielectric loss and heat generating property, and good temperature property even though lead is not substantially used. A dielectric composition of the first aspect includes a, Ca, Bi, Ti, and Sr, wherein the dielectric composition includes two phases having different Sr characteristic X ray intensities when a characteristic X ray intensity derived from Sr is measured by EPMA, and when Sr1 represents the characteristic X ray intensity derived from Sr of a first phase measured by EPMA and Sr2 represents the characteristic X ray intensity derived from Sr of a second phase measured by EPMA, a ratio (Sr2/Sr1) of Sr2 with respect to Sr1 satisfies 2 or larger.
    Type: Application
    Filed: March 19, 2019
    Publication date: October 3, 2019
    Applicant: TDK CORPORATION
    Inventors: Daisuke OHTSU, Taku MASAI, Liu HAILONG, Liang LIPING
  • Patent number: 10003009
    Abstract: A composite piezoelectric ceramic includes a compact of crystal particles including at least one of potassium niobate (KNbO3) and sodium niobate (NaNbO3) and optionally further including lithium niobate (LiNbO3), and a layer containing barium titanate (BaTiO3) that is disposed on the surface of the compact while forming a heterojunction with the compact. A piezoelectric device includes the composite piezoelectric ceramic.
    Type: Grant
    Filed: February 27, 2015
    Date of Patent: June 19, 2018
    Assignee: TDK CORPORATION
    Inventors: Masahito Furukawa, Yoshikazu Shimura, Taku Masai, Satoshi Wada
  • Patent number: 9831418
    Abstract: The present invention aims to provide a piezoelectric composition and a piezoelectric element. In the piezoelectric composition, the main component is represented by the following formula with a perovskite type structure, (Bi(0.5x+y+z)Na0.5x)m(Ti(x+0.5y)Mg0.5yMez)O3 wherein, 0.05?x?0.7, 0.01?y?0.7, 0.01?z?0.6, 0.75?m?1.0, x+y+z=1 and the transition metal element Me is any one or more selected from the group consisting of Mn, Cr, Fe and Co.
    Type: Grant
    Filed: January 30, 2015
    Date of Patent: November 28, 2017
    Assignee: TDK CORPORATION
    Inventors: Taku Masai, Masahito Furukawa, Hiroki Katoh
  • Patent number: 9780294
    Abstract: The present invention aims to provide an excellent piezoelectric composition and an excellent piezoelectric element if the piezoelectric properties especially a high spontaneous polarization and a sufficiently high resistivity, the low pollution, the environment and the ecology are considered. In the piezoelectric composition, the main component contains the substance represented by the following formula with a perovskite-typed structure, (Bi(0.5x+y+z)Na0.5x)m(Tix+0.5yMg0.5yAlz)O3. Wherein, 0.01?x?0.8, 0.2?y?0.8, 0.01?z?0.6, 0.75?m?1.0, and x+y+z=1.
    Type: Grant
    Filed: November 7, 2014
    Date of Patent: October 3, 2017
    Assignee: TDK CORPORATION
    Inventors: Taku Masai, Keisuke Teranishi, Masahito Furukawa
  • Patent number: 9537083
    Abstract: Provided is a piezoelectric composition containing a major component that is a perovskite-type oxide which is represented by the general formula ABO3, which contains no Pb, and which has A-sites containing Bi, Na, and K and B-sites containing Ti. The Ti is partly substituted with a transition metal element Me that is at least one selected from the group consisting of Mn, Cr, Fe, and Co. The content of Bi and the transition metal element Me in the perovskite-type oxide, which is the major component, is 6 mole percent to 43 mole percent in terms of Biu1MeO3.
    Type: Grant
    Filed: March 7, 2014
    Date of Patent: January 3, 2017
    Assignee: TDK CORPORATION
    Inventors: Taku Masai, Masamitsu Haemori, Masahito Furukawa, Junichi Yamazaki, Kouhei Ohhashi
  • Patent number: 9487445
    Abstract: A novel ceramic composition having a high relative dielectric constant. A ceramic composition includes a unit cell having at least two crystal structures selected from the group made of a monoclinic crystal, a tetragonal crystal, an orthorhombic crystal, and a rhombohedral crystal, characterized in that when the crystal structures are represented by the symmetry notation according to the Glazer method, namely xn1yn2zn3, n1, n2, and n3 are at least one selected from the group made of + and ?, or at least two selected from the group made of 0, +, and ?. By using this ceramic composition, a novel ceramic composition having a high relative dielectric constant can be obtained.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: November 8, 2016
    Assignee: TDK CORPORATION
    Inventors: Hidesada Natsui, Taku Masai, Sanshiro Aman
  • Patent number: 9437807
    Abstract: The present invention aims to provide a piezoelectric composition and a piezoelectric element containing the piezoelectric composition. In the piezoelectric composition, the main component contains a substance represented by the following formula with a perovskite structure, (Bi(0.5x+y+z)Na0.5x)m(Ti(x+0.5y)Mg0.5yAlkzCo(1?k)z)O3 0.15?x?0.7, 0.28?y?0.75, 0.02?z?0.30, 0.17?k?0.83, 0.75?m?1.0, and x+y+z=1.
    Type: Grant
    Filed: March 31, 2015
    Date of Patent: September 6, 2016
    Assignee: TDK CORPORATION
    Inventors: Yuko Saya, Taku Masai, Masahito Furukawa, Masamitsu Haemori
  • Publication number: 20160141486
    Abstract: Provided is a piezoelectric composition containing a major component that is a perovskite-type oxide which is represented by the general formula ABO3, which contains no Pb, and which has A-sites containing Bi, Na, and K and B-sites containing Ti. The Ti is partly substituted with a transition metal element Me that is at least one selected from the group consisting of Mn, Cr, Fe, and Co. The content of Bi and the transition metal element Me in the perovskite-type oxide, which is the major component, is 6 mole percent to 43 mole percent in terms of Biu1MeO3.
    Type: Application
    Filed: March 7, 2014
    Publication date: May 19, 2016
    Applicant: TDK CORPORATION
    Inventors: Taku MASAI, Masamitsu HAEMORI, Masahito FURUKAWA, Junichi YAMAZAKI, Kouhei OHHASHI
  • Patent number: 9324931
    Abstract: A piezoelectric device includes a first electrode film, a piezoelectric film disposed on the first electrode film, and a second electrode film disposed on the piezoelectric film. At least one of the first and second electrode films is composed of an alloy, and a main component of the alloy is a metal selected from the group consisting of Ti, Al, Mg, and Zn. The piezoelectric film has a main composition represented by (K1-x-y-w-vNaxLiyBawSrv)m(Nb1-z-uTazZru)O3 (1), where x, y, z, w, v, u, and m in formula (1) satisfy 0.4<x?0.7, 0.02?y?0.11, 0.5?x+y<0.75, 0<z?0.28, 0<w?0.02, 0.02?v?0.11, 0.02?u?0.11, and 0.95?m<1.2, and contains 1% by mass or less of MnO relative to the main composition.
    Type: Grant
    Filed: May 14, 2013
    Date of Patent: April 26, 2016
    Assignee: TDK CORPORATION
    Inventors: Masahito Furukawa, Tomohisa Azuma, Taku Masai
  • Publication number: 20150353430
    Abstract: A novel ceramic composition having a high relative dielectric constant. A ceramic composition includes a unit cell having at least two crystal structures selected from the group made of a monoclinic crystal, a tetragonal crystal, an orthorhombic crystal, and a rhombohedral crystal, characterized in that when the crystal structures are represented by the symmetry notation according to the Glazer method, namely xn1yn2zn3, n1, n2, and n3 are at least one selected from the group made of + and ?, or at least two selected from the group made of 0, +, and ?. By using this ceramic composition, a novel ceramic composition having a high relative dielectric constant can be obtained.
    Type: Application
    Filed: March 24, 2014
    Publication date: December 10, 2015
    Inventors: Hidesada NATSUI, Taku MASAI, Sanshiro AMAN
  • Publication number: 20150280105
    Abstract: The present invention aims to provide a piezoelectric composition and a piezoelectric element containing the piezoelectric composition. In the piezoelectric composition, the main component contains a substance represented by the following formula with a perovskite structure, (Bi(0.5x+y+z)Na0.5x)m(Ti(x+0.5y)Mg0.5yAlkzCo(1?k)z)O3 0.15?x?0.7, 0.28?y?0.75, 0.02?z?0.30, 0.17?k?0.83, 0.75?m?1.0, and x+y+z=1.
    Type: Application
    Filed: March 31, 2015
    Publication date: October 1, 2015
    Inventors: Yuko SAYA, Taku MASAI, Masahito FURUKAWA, Masamitsu HAEMORI
  • Publication number: 20150249201
    Abstract: A composite piezoelectric ceramic includes a compact of crystal particles including at least one of potassium niobate (KNbO3) and sodium niobate (NaNbO3) and optionally further including lithium niobate (LiNbO3), and a layer containing barium titanate (BaTiO3) that is disposed on the surface of the compact while forming a heterojunction with the compact. A piezoelectric device includes the composite piezoelectric ceramic.
    Type: Application
    Filed: February 27, 2015
    Publication date: September 3, 2015
    Inventors: Masahito FURUKAWA, Yoshikazu SHIMURA, Taku MASAI, Satoshi WADA
  • Publication number: 20150221858
    Abstract: The present invention aims to provide a piezoelectric composition and a piezoelectric element. In the piezoelectric composition, the main component is represented by the following formula with a perovskite type structure, (Bi(0.5x+y+z)Na0.5x)m(Ti(x+0.5y)Mg0.5yMez)O3 wherein, 0.05?x?0.7, 0.01?y?0.7, 0.01?z?0.6, 0.75?m?1.0, x+y+z=1 and the transition metal element Me is any one or more selected from the group consisting of Mn, Cr, Fe and Co.
    Type: Application
    Filed: January 30, 2015
    Publication date: August 6, 2015
    Inventors: Taku MASAI, Masahito FURUKAWA, Hiroki KATOH
  • Publication number: 20150129792
    Abstract: The present invention aims to provide an excellent piezoelectric composition and an excellent piezoelectric element if the piezoelectric properties especially a high spontaneous polarization and a sufficiently high resistivity, the low pollution, the environment and the ecology are considered. In the piezoelectric composition, the main component contains the substance represented by the following formula with a perovskite-typed structure, (Bi(0.5x+y+z)Na0.5x)m(Tix+0.5yMg0.5yAlz)O3. Wherein, 0.01?x?0.8, 0.2?y?0.8, 0.01?z?0.6, 0.75?m?1.
    Type: Application
    Filed: November 7, 2014
    Publication date: May 14, 2015
    Inventors: Taku MASAI, Keisuke TERANISHI, Masahito FURUKAWA
  • Patent number: 8956547
    Abstract: A piezoelectric compound having no occurrence of segregation or uneven structures as well as a piezoelectric element having excellent piezoelectric properties. The piezoelectric composition includes a main component that is a perovskite-typed oxide represented by formula of ABO3, wherein, one site includes Bi, Na, and another site includes Ti, and part of the Ti is substituted by transition metal element Me (Me is at least one element selected from the group consisting of Mn, Cr, Fe and Co), according to the conversion of BiMeO3, the content ratio of Bi and the transition metal element Me accounts for 6˜43 mol % relative to the whole perovskite-typed oxides as the main component.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: February 17, 2015
    Assignee: TDK Corporation
    Inventors: Taku Masai, Masahito Furukawa
  • Publication number: 20140339962
    Abstract: A piezoelectric device includes a first electrode film, a piezoelectric film disposed on the first electrode film, and a second electrode film disposed on the piezoelectric film. At least one of the first and second electrode films is composed of an alloy, and a main component of the alloy is a metal selected from the group consisting of Ti, Al, Mg, and Zn. The piezoelectric film has a main composition represented by (K1-x-y-w-vNaxLiyBawSrv)m(Nb1-z-uTazZru)O3 (1), where x, y, z, w, v, u, and m in formula (1) satisfy 0.4<x?0.7, 0.02?y?0.11, 0.5?x+y<0.75, 0<z?0.28, 0<w?0.02, 0.02?v?0.11, 0.02?u?0.11, and 0.95?m<1.2, and contains 1% by mass or less of MnO relative to the main composition.
    Type: Application
    Filed: May 14, 2013
    Publication date: November 20, 2014
    Applicant: TDK CORPORATION
    Inventors: Masahito FURUKAWA, Tomohisa AZUMA, Taku MASAI
  • Publication number: 20140339458
    Abstract: A piezoelectric ceramic contains a major proportion of potassium sodium niobate and has a carbon content after firing of 55 to 1,240 ppm by mass.
    Type: Application
    Filed: May 14, 2013
    Publication date: November 20, 2014
    Applicant: TDK CORPORATION
    Inventors: Masahito FURUKAWA, Tomohisa AZUMA, Taku MASAI, Yasuhiro AIDA
  • Patent number: 7973630
    Abstract: A thin film magnetic device is provided, in which magnetic permeability in a high frequency range can be easily improved. Scratch-like grooves extending along an extending direction of a coil (for example, a Y-axis direction being an extending direction of a second coil part) are formed at least one side of a surface and a back of each of a lower magnetic film and an upper magnetic film. A magnetization direction of anisotropic magnetization is controlled in each of formation areas of the scratch-like grooves (formation areas of lower magnetic films and upper magnetic films), and therefore displacement (rotation) of the magnetization direction of the anisotropic magnetization is pinned by the scratch-like grooves. Consequently, certain magnetic permeability is kept even in a high frequency range. Moreover, such formation of the scratch-like grooves may not cause complexity in manufacturing process.
    Type: Grant
    Filed: January 29, 2008
    Date of Patent: July 5, 2011
    Assignee: TDK Corporation
    Inventors: Taku Masai, Ryuji Hashimoto
  • Patent number: 7900350
    Abstract: A circuit element comprises a wiring board; the wiring board comprises a substrate and a wiring formed on the substrate, and a lid joined on the substrate containing a part of the wiring with a binder and making a sealed space above the substrate, wherein if a spot of the wiring joined with the lid by a binder is a spot of junction, a flank of both flanks of the wiring comprise bends in the spot of junction.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: March 8, 2011
    Assignee: OMRON Corporation
    Inventors: Taku Masai, Koji Sano