Patents by Inventor Kenichi Ishizu

Kenichi Ishizu 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: 20220185739
    Abstract: A silica-titania composite oxide powder of the present invention has an average particle diameter D (?m) of 0.1 ?m or more to 3.0 ?m or less, an average refractive index of 1.47 or more at a measurement wavelength of 589 nm, and a minimum absorbance S measured from a dispersion of 30 mass % of silica-titania composite oxide particles in a liquid having the same refractive index as the average refractive index, the minimum absorbance S satisfying the relationship “S<0.026?0.008×D.
    Type: Application
    Filed: March 12, 2020
    Publication date: June 16, 2022
    Applicant: TOKUYAMA CORPORATION
    Inventor: Kenichi ISHIZU
  • Patent number: 9809682
    Abstract: Provided are a poly alkylsilsesquioxane fine particle having hydrophobicity and having a small particle diameter, an external additive for toner and a dry toner for electrophotography each using the same, and a method of manufacturing a hydrophobized spherical polyalkylsilsesquioxane fine particle. The hydrophobized spherical poly alkylsilsesquioxane fine particle has a mass-based median diameter in a centrifugal sedimentation method within the range of from 0.05 ?m to 0.3 ?m. The fine particle is produced through, for example, at least a process involving: mixing a raw material solution prepared using an alkyl trialkoxysilane with an alkaline aqueous medium to obtain a polycondensation reaction liquid; mixing the polycondensation reaction liquid with an aqueous solution to obtain a fine particle dispersion liquid; and blending a hydrophobizing agent in the fine particle dispersion liquid.
    Type: Grant
    Filed: January 7, 2015
    Date of Patent: November 7, 2017
    Assignee: TOKUYAMA CORPORATION
    Inventors: Kenichi Ishizu, Yohei Chikashige, Tadaharu Komatsubara
  • Publication number: 20160319077
    Abstract: Provided are a poly alkylsilsesquioxane fine particle having hydrophobicity and having a small particle diameter, an external additive for toner and a dry toner for electrophotography each using the same, and a method of manufacturing a hydrophobized spherical polyalkylsilsesquioxane fine particle. The hydrophobized spherical poly alkylsilsesquioxane fine particle has a mass-based median diameter in a centrifugal sedimentation method within the range of from 0.05 ?m to 0.3 ?m. The fine particle is produced through, for example, at least a process involving: mixing a raw material solution prepared using an alkyl trialkoxysilane with an alkaline aqueous medium to obtain a polycondensation reaction liquid; mixing the polycondensation reaction liquid with an aqueous solution to obtain a fine particle dispersion liquid; and blending a hydrophobizing agent in the fine particle dispersion liquid.
    Type: Application
    Filed: January 7, 2015
    Publication date: November 3, 2016
    Inventors: Kenichi ISHIZU, Yohei CHIKASHIGE, Tadaharu KOMATSUBARA
  • Patent number: 9079777
    Abstract: The present invention relates to a method for producing inorganic oxide particles, comprising at least the following steps of: coagulating a dispersion obtained by carrying out the hydrolysis reaction and the polycondensation reaction of a metal alkoxide in the presence of a basic catalyst; filtering the dispersion to obtain particles; and drying the particles, wherein the step of coagulating the dispersion is carried out by adding a coagulant comprising at least one compound selected from the group consisting of carbon dioxide, ammonium carbonate, ammonium hydrogen carbonate and ammonium carbamate to the dispersion. The inorganic oxide particles obtained by the method of the present invention have high purity and are excellent in flowability.
    Type: Grant
    Filed: November 5, 2014
    Date of Patent: July 14, 2015
    Assignee: TOKUYAMA CORPORATION
    Inventors: Takayuki Maehara, Tadaharu Komatsubara, Yuya Yamano, Kenichi Ishizu, Makoto Sato, Hiroaki Taira, Hiroshi Kato
  • Patent number: 9000202
    Abstract: The present invention relates to a method for producing inorganic oxide particles, comprising at least the following steps of: coagulating a dispersion obtained by carrying out the hydrolysis reaction and the polycodensation reaction of a metal alkoxide in the presence of a basic catalyst; filtering the dispersion to obtain particles; and drying the particles, wherein the step of coagulating the dispersion is carried out by adding a coagulant comprising at least one compound selected from the group consisting of carbon dioxide, ammonium carbonate, ammonium hydrogen carbonate and ammonium carbamate to the dispersion. The inorganic oxide particles obtained by the method of the present invention have high purity and are excellent in flowability.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: April 7, 2015
    Assignee: Tokuyama Corporation
    Inventors: Takayuki Maehara, Tadaharu Komatsubara, Yuya Yamano, Kenichi Ishizu, Makoto Sato, Hiroaki Taira, Hiroshi Kato
  • Publication number: 20150056119
    Abstract: The present invention relates to a method for producing inorganic oxide particles, comprising at least the following steps of: coagulating a dispersion obtained by carrying out the hydrolysis reaction and the polycondensation reaction of a metal alkoxide in the presence of a basic catalyst; filtering the dispersion to obtain particles; and drying the particles, wherein the step of coagulating the dispersion is carried out by adding a coagulant comprising at least one compound selected from the group consisting of carbon dioxide, ammonium carbonate, ammonium hydrogen carbonate and ammonium carbamate to the dispersion. The inorganic oxide particles obtained by the method of the present invention have high purity and are excellent in flowability.
    Type: Application
    Filed: November 5, 2014
    Publication date: February 26, 2015
    Applicant: TOKUYAMA CORPORATION
    Inventors: Takayuki MAEHARA, Tadaharu KOMATSUBARA, Yuya YAMANO, Kenichi ISHIZU, Makoto SATO, Hiroaki TAIRA, Hiroshi KATO
  • Publication number: 20120323030
    Abstract: The present invention relates to a method for producing inorganic oxide particles, comprising at least the following steps of: coagulating a dispersion obtained by carrying out the hydrolysis reaction and the polycodensation reaction of a metal alkoxide in the presence of a basic catalyst; filtering the dispersion to obtain particles; and drying the particles, wherein the step of coagulating the dispersion is carried out by adding a coagulant comprising at least one compound selected from the group consisting of carbon dioxide, ammonium carbonate, ammonium hydrogen carbonate and ammonium carbamate to the dispersion. The inorganic oxide particles obtained by the method of the present invention have high purity and are excellent in flowability.
    Type: Application
    Filed: February 18, 2011
    Publication date: December 20, 2012
    Inventors: Takayuki Maehara, Tadaharu Komatsubara, Yuya Yamano, Kenichi Ishizu, Makoto Sato, Hiroaki Taira, Hiroshi Kato
  • Patent number: 6417264
    Abstract: Provided is a cationic polymer-modified silica dispersion which comprises silica fine particles having an average particle diameter of less than 200 nm and a cationic polymer and which does not bring about coagulation of the silica particles. The above dispersion which is diluted to a solid concentration of 1.5% by weight is characterized by having a light scattering index (n value) of 2.0 or more. The above dispersion can be produced by oppositely-colliding a mixed solution obtained by mixing silica with a cationic polymer in a polar solvent at a treating pressure of 300 kgf/cm2 or more or passing it through an orifice under a condition that a pressure difference between the inlet side and the outlet side of the orifice is 300 kgf cm2 or more.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: July 9, 2002
    Assignee: Tokuyama Corporation
    Inventors: Hiroyuki Kono, Kenji Fukunaga, Kenichi Ishizu, Yoshinori Tagashira