Patents by Inventor Keishi Taniguchi

Keishi Taniguchi 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: 20150152275
    Abstract: A method for preparing a pigment dispersion including subjecting a mixture including at least a pigment, a dispersant and water to a first dispersion treatment using a media mill to prepare a first dispersion; and then subjecting the first dispersion to a second dispersion treatment using a media-less mill to prepare the pigment dispersion, wherein the pigment in the pigment dispersion has an average particle diameter (D50) of from 20 to 130 nm for pigments except carbon black or from 70 to 180 for carbon black, and the standard deviation of the particle diameter of the pigment is less than the average particle diameter (D50) for pigments except carbon black or one half of the average particle diameter (D50) for carbon black. A pigment dispersion prepared by the method. An inkjet ink including the pigment dispersion and one member selected from water, water soluble organic solvents, and surfactants.
    Type: Application
    Filed: February 11, 2015
    Publication date: June 4, 2015
    Inventors: Minoru HAKIRI, Keishi TANIGUCHI, Shin HASEGAWA, Yuji NATORI, Yasuyuki HOSOGI, Shigeo HATADA
  • Patent number: 8680175
    Abstract: The present invention provides an inkjet ink containing at least a colorant, water, a water insoluble resin, a fluorine surfactant, and a polyether-modified silicone oil, wherein the polyether-modified silicone oil has a hydrophobic value of 0.40 to 1.5, and the hydrophobic value is expressed by Equation 1; Hydrophobic value=A/B??Equation 1 where “A” represents an integration value of a peak area from 0 ppm to 0.3 ppm in a 1H-NMR spectrum of the polyether-modified silicone oil using tetramethylsilane as a reference substance; and “B” represents an integration value of a peak area from 3.5 ppm to 4.0 ppm in the 1H-NMR spectrum.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: March 25, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigeo Hatada, Keishi Taniguchi, Shigeru Kusakata, Ichiroh Fujii, Akihiko Matsuyama, Yuuki Yokohama
  • Publication number: 20130023614
    Abstract: The present invention provides an inkjet ink containing at least a colorant, water, a water insoluble resin, a fluorine surfactant, and a polyether-modified silicone oil, wherein the polyether-modified silicone oil has a hydrophobic value of 0.40 to 1.5, and the hydrophobic value is expressed by Equation 1; Hydrophobic value=A/B??Equation 1 where “A” represents an integration value of a peak area from 0 ppm to 0.3 ppm in a 1H-NMR spectrum of the polyether-modified silicone oil using tetramethylsilane as a reference substance; and “B” represents an integration value of a peak area from 3.5 ppm to 4.0 ppm in the 1H-NMR spectrum.
    Type: Application
    Filed: September 14, 2012
    Publication date: January 24, 2013
    Inventors: Shigeo HATADA, Keishi TANIGUCHI, Shigeru KUSAKATA, Ichiroh FUJII, Akihiko MATSUYAMA, Yuuki YOKOHAMA
  • Patent number: 8317913
    Abstract: The present invention provides an inkjet ink containing at least a colorant, water, a water insoluble resin, a fluorine surfactant, and a polyether-modified silicone oil, wherein the polyether-modified silicone oil has a hydrophobic value of 0.40 to 1.5, and the hydrophobic value is expressed by Equation 1: Hydrophobic value=A/B??Equation 1 where “A” represents an integration value of a peak area from 0 ppm to 0.3 ppm in a 1H-NMR spectrum of the polyether-modified silicone oil using tetramethylsilane as a reference substance; and “B” represents an integration value of a peak area from 3.5 ppm to 4.0 ppm in the 1H-NMR spectrum.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: November 27, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigeo Hatada, Keishi Taniguchi, Shigeru Kusakata, Ichiroh Fujii, Akihiko Matsuyama, Yuuki Yokohama
  • Patent number: 8246156
    Abstract: The object of the present invention is to provide a water-based pigment dispersion containing a pigment, a dispersing agent, a resin emulsion, and water, the water-based pigment dispersion is subjected to a heat treatment. The present invention also provides a water-based pigment ink containing the water-based pigment dispersion, a dispersing agent, a resin emulsion, and water.
    Type: Grant
    Filed: August 12, 2010
    Date of Patent: August 21, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Shin Hasegawa, Keishi Taniguchi, Minoru Hakiri, Yasuyuki Hosogi, Yuji Natori, Shigeo Hatada
  • Publication number: 20100302306
    Abstract: The object of the present invention is to provide a water-based pigment dispersion containing a pigment, a dispersing agent, a resin emulsion, and water, the water-based pigment dispersion is subjected to a heat treatment. The present invention also provides a water-based pigment ink containing the water-based pigment dispersion, a dispersing agent, a resin emulsion, and water.
    Type: Application
    Filed: August 12, 2010
    Publication date: December 2, 2010
    Inventors: Shin HASEGAWA, Keishi Taniguchi, Minoru Hakiri, Yasuyuki Hosogi, Yuji Natori, Shigeo Hatada
  • Patent number: 7815301
    Abstract: The object of the present invention is to provide a water-based pigment dispersion containing a pigment, a dispersing agent, a resin emulsion, and water, the water-based pigment dispersion is subjected to a heat treatment. The present invention also provides a water-based pigment ink containing the water-based pigment dispersion, a dispersing agent, a resin emulsion, and water.
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: October 19, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Shin Hasegawa, Keishi Taniguchi, Minoru Hakiri, Yasuyuki Hosogi, Yuji Natori, Shigeo Hatada
  • Patent number: 7798629
    Abstract: The present invention provides a pigment dispersion that contains a carbon black, a dispersing agent and water, wherein the carbon black is any one of a channel black and a gas black, the dispersing agent is a sodium naphthalenesulfonate formalin condensate, and the total content of a dimer, a trimer and a tetramer of naphthalenesulfonate in the sodium naphthalenesulfonate formalin condensate is 20% by weight to 80% by weight. The present invention also provides an inkjet ink using the pigment dispersion.
    Type: Grant
    Filed: August 10, 2007
    Date of Patent: September 21, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Minoru Hakiri, Keishi Taniguchi, Yuji Natori, Yasuyuki Hosogi, Shigeo Hatada, Shin Hasegawa
  • Publication number: 20090202935
    Abstract: A carrier including magnetic core particles and a coating layer, wherein the coating layer is formed by applying a coating liquid containing at least colloidal silica, a condensate of alkoxysilane represented by General Formula (1) and a solvent onto the core particles; an amount of colloidal silica contained in the coating layer is less than 60% by mass; and a ratio (h/Dw) of a thickness (h) of the coating layer to a weight average particle diameter (Dw) of the carrier is more than 0.01, wherein the carrier is used in a two-component developer together with a toner produced through aqueous granulation and containing at least a colorant, a binder resin and a releasing agent, and wherein an amount of the releasing agent present in a region from a surface of the toner to a depth of 0.3 ?m is less than 4% by mass as measured through FTIR-ATR spectroscopy.
    Type: Application
    Filed: February 5, 2009
    Publication date: August 13, 2009
    Inventors: Yoshihiro Moriya, Keishi Taniguchi, Akihiro Kotsugai, Ryota Inoue, Shingo Sakashita
  • Publication number: 20090047431
    Abstract: The present invention provides an inkjet ink containing at least a colorant, water, a water insoluble resin, a fluorine surfactant, and a polyether-modified silicone oil, wherein the polyether-modified silicone oil has a hydrophobic value of 0.40 to 1.5, and the hydrophobic value is expressed by Equation 1: Hydrophobic value=A/B??Equation 1 where “A” represents an integration value of a peak area from 0 ppm to 0.3 ppm in a 1H-NMR spectrum of the polyether-modified silicone oil using tetramethylsilane as a reference substance; and “B” represents an integration value of a peak area from 3.5 ppm to 4.0 ppm in the 1H-NMR spectrum.
    Type: Application
    Filed: August 13, 2008
    Publication date: February 19, 2009
    Inventors: Shigeo HATADA, Keishi Taniguchi, Shigeru Kusakata, Ichiroh Fujii, Akihiko Matsuyama, Yuuki Yokohama
  • Publication number: 20080036840
    Abstract: The present invention provides a pigment dispersion that contains a carbon black, a dispersing agent and water, wherein the carbon black is any one of a channel black and a gas black, the dispersing agent is a sodium naphthalenesulfonate formalin condensate, and the total content of a dimer, a trimer and a tetramer of naphthalenesulfonate in the sodium naphthalenesulfonate formalin condensate is 20% by weight to 80% by weight. The present invention also provides an inkjet ink using the pigment dispersion.
    Type: Application
    Filed: August 10, 2007
    Publication date: February 14, 2008
    Inventors: Minoru Hakiri, Keishi Taniguchi, Yuji Natori, Yasuyuki Hosogi, Shigeo Hatada, Shin Hasegawa
  • Publication number: 20080036830
    Abstract: An ink-jet ink including a pigment a dispersant, a water, a particulate resin (A) dyed with a fluorescent dye and having an average particle diameter of from 50 to 200 nm, and an emulsion of a self-emulsifiable polyurethane; and a method for preparing the ink-jet ink, an ink cartridge containing the ink-jet ink, an image forming method using the ink-jet ink, and an image formed with the ink-jet ink.
    Type: Application
    Filed: August 6, 2007
    Publication date: February 14, 2008
    Inventors: Yuji NATORI, Keishi TANIGUCHI, Minoru HAKIRI, Yasuyuki HOSOGI, Shigeo HATADA, Shinn HASEGAWA
  • Patent number: 7152968
    Abstract: An ink composition containing a colorant, a humectant, water, and a water-soluble substance that begins to be condensation-polymerized as the water evaporates is ejected such that drops of the ink composition are adhered onto a print material 41 whose surface is acidic, whereby an image is formed on the print material 41.
    Type: Grant
    Filed: June 10, 2003
    Date of Patent: December 26, 2006
    Assignees: Matsushita Electric Industrial Co., Ltd., Ricoh Co., Ltd.
    Inventors: Mamoru Soga, Hidekazu Arase, Masaichiro Tatekawa, Keishi Taniguchi, Tsutomu Matsuda, Masashi Ito, Takamichi Enomoto
  • Publication number: 20060272543
    Abstract: A method for preparing a pigment dispersion including subjecting a mixture including at least a pigment, a dispersant and water to a first dispersion treatment using a media mill to prepare a first dispersion; and then subjecting the first dispersion to a second dispersion treatment using a media-less mill to prepare the pigment dispersion, wherein the pigment in the pigment dispersion has an average particle diameter (D50) of from 20 to 130 nm for pigments except carbon black or from 70 to 180 for carbon black, and the standard deviation of the particle diameter of the pigment is less than the average particle diameter (D50) for pigments except carbon black or one half of the average particle diameter (D50) for carbon black. A pigment dispersion prepared by the method. An inkjet ink including the pigment dispersion and one member selected from water, water soluble organic solvents, and surfactants.
    Type: Application
    Filed: June 1, 2006
    Publication date: December 7, 2006
    Inventors: Minoru Hakiri, Keishi Taniguchi, Shin Hasegawa, Yuji Natori, Yasuyuki Hosogi, Shigeo Hatada
  • Publication number: 20060209149
    Abstract: The object of the present invention is to provide a water-based pigment dispersion containing a pigment, a dispersing agent, a resin emulsion, and water, the water-based pigment dispersion is subjected to a heat treatment. The present invention also provides a water-based pigment ink containing the water-based pigment dispersion, a dispersing agent, a resin emulsion, and water.
    Type: Application
    Filed: March 15, 2006
    Publication date: September 21, 2006
    Inventors: Shin Hasegawa, Keishi Taniguchi, Minoru Hakiri, Yasuyuki Hosogi, Yuji Natori, Shigeo Hatada
  • Patent number: 7101919
    Abstract: An inkjet ink including water; a particulate pigment; a dispersant; and an emulsion, wherein the particulate pigment has an average particle diameter (D50) not greater than 100 nm, and the standard deviation of particle diameter distribution of the particulate pigment is less than one half of the average particle diameter (D50). An inkjet cartridge containing the inkjet ink. An inkjet recording apparatus including the inkjet cartridge and a carriage configured to carry the ink cartridge. An inkjet recording method including discharging the inkjet ink from a nozzle of a recording head to form an ink image on a recording paper. An image formed on a recording material in accordance with the inkjet recording method.
    Type: Grant
    Filed: October 28, 2003
    Date of Patent: September 5, 2006
    Assignee: Ricoh Company Limited
    Inventors: Shin Hasegawa, Keishi Taniguchi, Minoru Hakiri, Yasuyuki Hosogi
  • Patent number: 6929686
    Abstract: In an ink composition used for inkjet recording which contains a colorant, a humectant, water, and a water-soluble substance that begins to be condensation-polymerized as the water evaporates, a condensation-polymerization accelerating agent for accelerating the condensation-polymerization of the water-soluble substance is further contained.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: August 16, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Mamoru Soga, Hidekazu Arase, Masaichiro Tatekawa, Keishi Taniguchi, Tsutomu Matsuda, Masashi Ito, Takamichi Enomoto
  • Publication number: 20050087105
    Abstract: A method for manufacturing a composition including: mixing a basic material with a pigment dispersion including at least a pigment and water; and then subjecting the mixture of the basic material and pigment dispersion to a heat treatment. This composition is useful as an inkjet ink composition. An inkjet ink composition including at least pigment, water and a basic material, and has a pH of from 6.5 to 11.0 is also provided. An image forming method including discharging the composition from a nozzle to form an ink image on a receiving material is provided.
    Type: Application
    Filed: November 18, 2004
    Publication date: April 28, 2005
    Applicant: RICOH COMPANY, LTD.
    Inventors: Keishi Taniguchi, Shigeo Hatada
  • Patent number: 6881251
    Abstract: A method for manufacturing a composition including: mixing a basic material with a pigment dispersion including at least a pigment and water; and then subjecting the mixture of the basic material and pigment dispersion to a heat treatment. This composition is useful as an inkjet ink composition. An inkjet ink composition including at least pigment, water and a basic material, and has a pH of from 6.5 to 11.0 is also provided. An image forming method including discharging the composition from a nozzle to form an ink image on a receiving material is provided.
    Type: Grant
    Filed: December 5, 2002
    Date of Patent: April 19, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Keishi Taniguchi, Shigeo Hatada
  • Patent number: 6814792
    Abstract: A pigment dispersion including a pigment, a dispersant, and a dispersion medium including water, wherein the dispersant includes a compound having the following formula (1): wherein R1 represents an alkyl group having from 1 to 20 carbon atoms, a phenyl group, a substituted phenyl group or a naphthyl group; k is 0 or an integer of from 1 to 7; A1 and A2 independently represent an oxyethylene unit, an oxypropylene unit or a combination of an oxyethylene unit and an oxypropylene unit; and h and j are independently 0 or a positive integer, wherein the total number of h and j is from 31 to 100.
    Type: Grant
    Filed: June 19, 2002
    Date of Patent: November 9, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Keishi Taniguchi, Shigeo Hatada