Patents by Inventor Kazumi Ohtaki

Kazumi Ohtaki 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: 10233110
    Abstract: A material set for manufacturing a glass object includes a powder material including glass and a first water soluble resin; and a liquid material including water and a second water soluble resin having a mass average molecular weight of less than 50,000.
    Type: Grant
    Filed: June 9, 2016
    Date of Patent: March 19, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeo Yamaguchi, Hitoshi Iwatsuki, Kazumi Ohtaki, Takuya Saito, Teruki Kusahara
  • Patent number: 10030154
    Abstract: A powder material for three-dimensional modeling includes a base particle and a resin including a first water soluble resin and a second water soluble resin, wherein a first aqueous solution of the first water soluble resin having a concentration of two percent by mass has a thermally reversible sol-gel phase transition and is gelated at temperatures higher than a first phase transition temperature of the first aqueous solution.
    Type: Grant
    Filed: March 17, 2016
    Date of Patent: July 24, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuru Naruse, Yasuo Suzuki, Nozomu Tamoto, Yasuyuki Yamashita, Hitoshi Iwatsuki, Kazumi Ohtaki
  • Patent number: 9873228
    Abstract: A powder material for three-dimensional modeling includes a base particle and a resin covering the base particle, wherein the resin has a first absorption peak in the range of from 1,141 cm?1 to 1,145 cm?1 and a second absorption peak in the range of from 1,089 cm?1 to 1,093 cm?1 in an infrared absorption spectrum and the intensity ratio of the first absorption peak to the second absorption peak is from 0.40 to 0.70.
    Type: Grant
    Filed: March 9, 2016
    Date of Patent: January 23, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuo Suzuki, Mitsuru Naruse, Hitoshi Iwatsuki, Nozomu Tamoto, Kazumi Ohtaki, Yasuyuki Yamashita
  • Patent number: 9782935
    Abstract: A powder material for three-dimensional modeling includes a base particle and a coverage film including an organic material. The coverage film covers the base particle. The powder material is used for three dimensional modeling and when the coverage film is dissolved in a solvent to prepare a solution and the solution is formed into a coated film on a smooth surface, the coated film has a wetting tension of from 22 mN/m to 28 mN/m.
    Type: Grant
    Filed: March 9, 2016
    Date of Patent: October 10, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuyuki Yamashita, Yasuo Suzuki, Mitsuru Naruse, Nozomu Tamoto, Shigenori Yaguchi, Hitoshi Iwatsuki, Kazumi Ohtaki
  • Patent number: 9708502
    Abstract: A powder for 3D modeling includes a base particle and a resin having a functional group represented by the following Chemical formula 1, where A1 represents O or NH and R1, R2, and R3 each, independently represent CH3, C2H5, C3H7, or C4H9. The base particle is covered with the resin.
    Type: Grant
    Filed: December 2, 2015
    Date of Patent: July 18, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuru Naruse, Nozomu Tamoto, Yasuo Suzuki, Hitoshi Iwatsuki, Yasuyuki Yamashita, Kazumi Ohtaki
  • Publication number: 20160368806
    Abstract: A material set for manufacturing a glass object includes a powder material including glass and a first water soluble resin; and a liquid material including water and a second water soluble resin having a mass average molecular weight of less than 50
    Type: Application
    Filed: June 9, 2016
    Publication date: December 22, 2016
    Inventors: Takeo YAMAGUCHI, Hitoshi IWATSUKI, Kazumi OHTAKI, Takuya SAITO, Teruki KUSAHARA
  • Publication number: 20160288206
    Abstract: A powder material for three-dimensional modeling includes a base material and a resin covering the base material, wherein the covering factor by the resin is 15 percent or more and the aspect ratio of the powder material is 0.90 or greater as calculated according to the following relation 1. Aspect ratio (average)=X1×Y1/100+X2×Y2/100+ . . . +Xn×Yn/100,??Relation 1 In the Relation 1, Y1+Y2+ . . . +Yn=100 (percent), Xn represents the aspect ratio (minor axis/major axis), Yn represents an existence ratio (percent) of a particle having an aspect ratio of Xn, and n is 15,000 or greater.
    Type: Application
    Filed: March 23, 2016
    Publication date: October 6, 2016
    Inventors: Kazumi OHTAKI, Hitoshi Iwatsuki, Yasuyuki Yamashita, Mitsuru Naruse, Yasuo Suzuki, Nozomu Tamoto
  • Publication number: 20160272817
    Abstract: A powder material for three-dimensional modeling includes a base particle and a resin including a first water soluble resin and a second water soluble resin, wherein a first aqueous solution of the first water soluble resin having a concentration of two percent by mass has a thermally reversible sol-gel phase transition and is gelated at temperatures higher than a first phase transition temperature of the first aqueous solution.
    Type: Application
    Filed: March 17, 2016
    Publication date: September 22, 2016
    Inventors: Mitsuru Naruse, Yasuo Suzuki, Nozomu Tamoto, Yasuyuki Yamashita, Hitoshi Iwatsuki, Kazumi Ohtaki
  • Publication number: 20160271879
    Abstract: A powder material for three-dimensional modeling includes a base particle and a coverage film including an organic material. The coverage film covers the base particle. The powder material is used for three dimensional modeling and when the coverage film is dissolved in a solvent to prepare a solution and the solution is formed into a coated film on a smooth surface, the coated film has a wetting tension of from 22 mN/m to 28 mN/m.
    Type: Application
    Filed: March 9, 2016
    Publication date: September 22, 2016
    Inventors: Yasuyuki YAMASHITA, Yasuo SUZUKI, Mitsuru NARUSE, Nozomu TAMOTO, Shigenori YAGUCHI, Hitoshi IWATSUKI, Kazumi OHTAKI
  • Publication number: 20160271877
    Abstract: A powder material for three-dimensional modeling includes a base particle and a resin covering the base particle, wherein the resin has a first absorption peak in the range of from 1,141 cm?1 to 1,145 cm?1 and a second absorption peak in the range of from 1,089 cm?1 to 1,093 cm?1 in an infrared absorption spectrum and the intensity ratio of the first absorption peak to the second absorption peak is from 0.40 to 0.70.
    Type: Application
    Filed: March 9, 2016
    Publication date: September 22, 2016
    Inventors: Yasuo SUZUKI, Mitsuru Naruse, Hitoshi Iwatsuki, Nozomu Tamoto, Kazumi Ohtaki, Yasuyuki Yamashita
  • Publication number: 20160177122
    Abstract: A powder for 3D modeling includes a base particle and a resin having a functional group represented by the following Chemical formula 1, where A1 represents O or NH and R1, R2, and R3 each, independently represent CH3, C2H5, C3H7, or C4H9. The base particle is covered with the resin.
    Type: Application
    Filed: December 2, 2015
    Publication date: June 23, 2016
    Inventors: Mitsuru NARUSE, Nozomu Tamoto, Yasuo Suzuki, Hitoshi Iwatsuki, Yasuyuki Yamashita, Kazumi Ohtaki
  • Patent number: 8968976
    Abstract: A method for regenerating a carrier core material for electrophotography, including: treating a carrier for electrophotography including a carrier core material for electrophotography and a coating layer on a surface of the carrier core material for electrophotography with an aqueous solution including an oxidant in a subcritical state or a supercritical state having a temperature of 280° C. or greater and a density of 0.20 g/cm3 or greater, wherein an amount of the oxidant in a total amount of the aqueous solution used in the treating is greater than 0.05 parts by mass with respect to 1 part by mass of the carrier for electrophotography to be treated in the treating.
    Type: Grant
    Filed: September 24, 2012
    Date of Patent: March 3, 2015
    Assignees: Ricoh Company, Ltd., National University Corporation Shizuoka University
    Inventors: Takayuki Shimizu, Kazumi Ohtaki, Shinichiro Yagi, Takeshi Sako, Idzumi Okajima
  • Publication number: 20130078567
    Abstract: A method for regenerating a carrier core material for electrophotography, including: treating a carrier for electrophotography including a carrier core material for electrophotography and a coating layer on a surface of the carrier core material for electrophotography with an aqueous solution including an oxidant in a subcritical state or a supercritical state having a temperature of 280° C. or greater and a density of 0.20 g/cm3 or greater, wherein an amount of the oxidant in a total amount of the aqueous solution used in the treating is greater than 0.05 parts by mass with respect to 1 part by mass of the carrier for electrophotography to be treated in the treating.
    Type: Application
    Filed: September 24, 2012
    Publication date: March 28, 2013
    Inventors: Takayuki Shimizu, Kazumi Ohtaki, Shinichiro Yagi, Takeshi Sako, Idzumi Okajima
  • Publication number: 20110136057
    Abstract: A method for treating an electrophotographic carrier, including treating, with supercritical pure water, the electrophotographic carrier containing at least a core material and a coating layer, so that the coating layer is separated from the core material, wherein the supercritical pure water is obtained by bringing, into a supercritical state, pure water having an electrical conductivity at 25° C. of 1 ?S·cm or lower.
    Type: Application
    Filed: December 3, 2010
    Publication date: June 9, 2011
    Inventors: Kazumi Ohtaki, Shinichiro Yagi, Masakazu Yashiro, Masayuki Kakimoto, Takayuki Shimizu
  • Patent number: 5565298
    Abstract: A method of producing a toner for developing latent electrostatic images is disclosed, which comprises the steps of dispersing resin particles comprising a resin in an organic solvent in which the resin is not dissolved; dissolving a dye in the organic solvent before or after dispersing the resin particles in the organic solvent to prepare a dispersion in which the resin particles and the dye are contained, thereby dying the resin particles with the dye; and removing the organic solvent from the dispersion, wherein the ratio of the solubility [D.sub.1 ] of the dye in the organic solvent to the solubility [D.sub.2 ] of the dye in the resin of the resin particles, [D.sub.1 ]/[D.sub.2 ], is not more than 0.5.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: October 15, 1996
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Suguro, Masaki Takatsugi, Hiroshi Yamashita, Kenkichi Muto, Kazumi Ohtaki, Yoshikazu Kaneko, Takayuki Hoshina
  • Patent number: 4888263
    Abstract: This invention relates to a color toner for electrophotography containing a coloring agent and a binder resin as the main components, said coloring agent comprising at least one of the anthraquinone derivatives expressed by the following general formula (I), ##STR1## wherein R.sup.1 represents hydrogen or an alkyl group having at least 6 carbon atoms and R.sup.2 represents hydrogen, an alkyl group having at least 6 carbon atoms or phenyl group.
    Type: Grant
    Filed: December 8, 1986
    Date of Patent: December 19, 1989
    Assignee: Ricoh Co., Ltd.
    Inventors: Masami Tomita, Yoshihiro Nomura, Noriaki Ide, Kazumi Ohtaki
  • Patent number: 4762763
    Abstract: This invention relates to a toner for developing an electrostatic latent image, which contains a coloring agent, a binder resin and a charge controlling agent as the main components, said charge controlling agent being a metal salt of salicylic acid or derivatives.
    Type: Grant
    Filed: December 8, 1986
    Date of Patent: August 9, 1988
    Assignee: Ricoh Co., Ltd.
    Inventors: Yoshihiro Nomura, Noriaki Ide, Kazumi Ohtaki, Masami Tomita, Hachiro Tosaka, Toshiki Nanya, Motoi Orihara, Shunichi Chiba, Satoru Inoue, Yasuo Asahina, Hiroyuki Fushimi
  • Patent number: 4599630
    Abstract: A two-color thermosensitive recording material using leuco dyes is disclosed, which is capable of forming two different colors when heated at different temperatures, black or blackish color at a low temperature and another color at a high temperature, comprising a support material, a high-temperature color-forming material overlaying the support material, a decolorization layer overlaying the high-temperature color-forming layer, and a low-temperature color-forming layer overlaying the decolorization layer, and when necessary, an intermediate layer interposed between the decolorization layer and the low-temperature color-forming layer, the decolorization layer containing an aliphatic amine or a morpholine derivative of the formula of ##STR1## which are fully defined in the specification, and the low-temperature color-forming layer containing as a color developer a thiourea derivatives of the formula, ##STR2## which is fully defined in the specification.
    Type: Grant
    Filed: November 9, 1984
    Date of Patent: July 8, 1986
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazumi Ohtaki, Hiroshi Sakamoto