Patents by Inventor Yuko Mitsuka

Yuko Mitsuka 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).

  • Publication number: 20230097120
    Abstract: A method of producing core/shell semiconductor nanoparticles, the method comprising a shell formation step of adding a solution of group VI element precursor while adding a solution of zinc branched chain carboxylate to a core particle-dispersed solution to allow the zinc branched chain carboxylate to react with the group VI element precursor in presence of the core particles for forming a shell containing zinc and the group VI element on surfaces of the core particles. The present invention can provide a simple semiconductor nanoparticle production method of producing core/shell semiconductor nanoparticles with excellent optical properties when two or more types of the shell precursors are used to produce the core/shell semiconductor nanoparticles.
    Type: Application
    Filed: February 16, 2021
    Publication date: March 30, 2023
    Inventors: Takafumi MORIYAMA, Yuko MITSUKA, Hirokazu SASAKI, Makoto KIDO
  • Patent number: 11505742
    Abstract: The purpose of the present invention to provide semiconductor nanoparticles substantially containing no Cd, and which have an increased absorption coefficient to blue light while maintaining high stability. Semiconductor nanoparticles having a core containing at least In and P, and a shell having one or more layers, wherein at least one layer of the shell is ZnSeTe (wherein Te/(Se+Te)=0.03 to 0.50); and the semiconductor nanoparticles cause, when the semiconductor nanoparticles are dispersed in a dispersion medium to yield a dispersion liquid with a concentration of 1 mg/mL in inorganic mass, the dispersion liquid to have an absorbance of 0.9 or higher with respect to light having a wavelength of 450 nm at an optical path length of 1 cm.
    Type: Grant
    Filed: September 5, 2019
    Date of Patent: November 22, 2022
    Assignee: SHOEI CHEMICAL INC.
    Inventors: Takafumi Moriyama, Hirokazu Sasaki, Makoto Kido, Keisuke Matsuura, Yuko Mitsuka, Naoki Sakura
  • Publication number: 20220325174
    Abstract: A semiconductor nanoparticle complex in which two or more ligands including an aliphatic ligand and a polar ligand are coordinated to a surface of a semiconductor nanoparticle, wherein: the ligands are composed of an organic group and a coordinating group; in the aliphatic ligand, the organic group is an aliphatic hydrocarbon group; the polar ligand includes a hydrophilic functional group in the organic group; a mass ratio of the aliphatic ligand to the polar ligand (aliphatic ligand/polar ligand) is 0.05 to 1.00; a ratio ({(XH)/L}×100) of a mass reduction rate of the semiconductor nanoparticle complex in a range of 350° C. or higher and 550° C. or lower in a thermogravimetric analysis (XH) to a mass fraction of all ligands in the semiconductor nanoparticle complex at room temperature (L) is 10 or more and 55 or less.
    Type: Application
    Filed: May 29, 2020
    Publication date: October 13, 2022
    Inventors: Makoto KIDO, Takafumi MORIYAMA, Hirokazu SASAKI, Yuko MITSUKA
  • Publication number: 20220315834
    Abstract: Provided is a semiconductor nanoparticle complex dispersion liquid in which semiconductor nanoparticles are dispersed in a polar dispersion medium at a high mass fraction, and in which high fluorescence quantum efficiency (QY) is maintained. A semiconductor nanoparticle complex dispersion liquid according to an embodiment includes a semiconductor nanoparticle complex dispersed in an organic dispersion medium, wherein: the semiconductor nanoparticle complex is composed of two or more ligands including an aliphatic thiol ligand and a polar ligand, and a semiconductor nanoparticle with the ligands coordinated to the surface thereof; the ligands are composed of an organic group and a coordinating group; the organic group of the polar ligand includes a hydrophilic functional group; and an SP value of the organic dispersion medium is 8.5 or more.
    Type: Application
    Filed: May 29, 2020
    Publication date: October 6, 2022
    Inventors: Makoto KIDO, Hirokazu SASAKI, Takafumi MORIYAMA, Yuko MITSUKA
  • Patent number: 11145792
    Abstract: The purpose of the present invention to provide a wavelength conversion layer containing semiconductor nanoparticles substantially containing no Cd, and which have an increased absorption coefficient to blue light while maintaining high stability. A wavelength conversion layer containing semiconductor nanoparticles, wherein the wavelength conversion layer can convert light having a wavelength of 450 nm to light having a peak wavelength of 500 nm to 550 nm, or light having a peak wavelength of 600 nm to 660 nm; each of the semiconductor nanoparticles contained in the wavelength conversion layer has a core and a shell having one or more layers; the core contains In and P; and at least one layer of the shell is ZnXTe (wherein X represents Se or S, or both Se and S).
    Type: Grant
    Filed: September 5, 2019
    Date of Patent: October 12, 2021
    Assignee: SHOEI CHEMICAL INC.
    Inventors: Takafumi Moriyama, Hirokazu Sasaki, Makoto Kido, Keisuke Matsuura, Yuko Mitsuka, Naoki Sakura
  • Publication number: 20200079997
    Abstract: The purpose of the present invention to provide semiconductor nanoparticles substantially containing no Cd, and which have an increased absorption coefficient to blue light while maintaining high stability. Semiconductor nanoparticles having a core containing at least In and P, and a shell having one or more layers, wherein at least one layer of the shell is ZnSeTe (wherein Te/(Se+Te)=0.03 to 0.50); and the semiconductor nanoparticles cause, when the semiconductor nanoparticles are dispersed in a dispersion medium to yield a dispersion liquid with a concentration of 1 mg/mL in inorganic mass, the dispersion liquid to have an absorbance of 0.9 or higher with respect to light having a wavelength of 450 nm at an optical path length of 1 cm.
    Type: Application
    Filed: September 5, 2019
    Publication date: March 12, 2020
    Inventors: Takafumi Moriyama, Hirokazu Sasaki, Makoto Kido, Keisuke Matsuura, Yuko Mitsuka, Naoki Sakura
  • Publication number: 20200083406
    Abstract: The purpose of the present invention to provide a wavelength conversion layer containing semiconductor nanoparticles substantially containing no Cd, and which have an increased absorption coefficient to blue light while maintaining high stability. A wavelength conversion layer containing semiconductor nanoparticles, wherein the wavelength conversion layer can convert light having a wavelength of 450 nm to light having a peak wavelength of 500 nm to 550 nm, or light having a peak wavelength of 600 nm to 660 nm; each of the semiconductor nanoparticles contained in the wavelength conversion layer has a core and a shell having one or more layers; the core contains In and P; and at least one layer of the shell is ZnXTe (wherein X represents Se or S, or both Se and S).
    Type: Application
    Filed: September 5, 2019
    Publication date: March 12, 2020
    Inventors: Takafumi Moriyama, Hirokazu Sasaki, Makoto Kido, Keisuke Matsuura, Yuko Mitsuka, Naoki Sakura