Patents by Inventor Michihiko Namba

Michihiko Namba 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: 20150283828
    Abstract: To provide an image forming method, including: a pre-treatment liquid application step for applying a pre-treatment liquid on a recording medium including a substrate and a coating layer at least on one surface of the substrate, wherein the pre-treatment liquid is applied on a surface of the recording layer with the coating layer! a drying step for drying the recording medium on which the pre-treatment liquid has been applied; and an image forming step for forming an image on the recording medium after drying by discharging a water-based ink by inkjet method, wherein the pre-treatment liquid includes a water-soluble cationic polymer, an ammonium salt of an organic acid and water, and wherein the water-based ink includes water and negatively charged colored particles including a colorant.
    Type: Application
    Filed: July 5, 2013
    Publication date: October 8, 2015
    Inventors: Shosuke Aoai, Tsutomu Maekawa, Michihiko Namba, Shinya Seno, Hiroshi Gotou, Akihiko Gotoh
  • Publication number: 20150258796
    Abstract: A cleaning liquid used for cleaning an ink flow channel in an inkjet recorder includes water; a hydrosoluble organic solvent; a compound having the following formula (1): wherein n represents an integer of from 1 to 40; and a compound having the following formula (2): wherein R1 and R2 independently represent an alkyl group having 3 to 6 carbon atoms; R3 and R4 independently represent a methyl group or an ethyl group; and n represents an integer of from 1 to 6.
    Type: Application
    Filed: March 2, 2015
    Publication date: September 17, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takashi Tamai, Michihiko Namba, Akihiko Gotoh
  • Publication number: 20150259567
    Abstract: An overcoating liquid contains a hydrodispersible polyurethane; a compound represented by Chemical formula 1: C6F13—CH2CH2O(CH2CH2O)nH, where n represents an integer of from 1 to 40; a compound represented by Chemical formula 2: HOR1R3C—(CH2)n—CR2R4OH, where R1 and R2 each, independently represent alkyl groups having three to six carbon atoms, R3 and R4 each, independently represent methyl groups or ethyl groups, and n represents an integer of from 1 to 6; and water, wherein the overcoating liquid is applied to the surface of a recording medium onto which inkjet ink is already discharged.
    Type: Application
    Filed: February 27, 2015
    Publication date: September 17, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Takashi Tamai, Michihiko Namba, Akihiko Gotoh
  • Patent number: 9085706
    Abstract: To provide an inkjet ink, which contains: water; a wetting agent; a surfactant; and a colorant, wherein the wetting agent contains at least an amide compound represented by the following structural formula (I):
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: July 21, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Gotou, Kiyofumi Nagai, Michihiko Namba, Hidetoshi Fujii, Yuuki Yokohama
  • Publication number: 20150174920
    Abstract: An inkjet recording method includes imparting a pre-processing fluid to a coated layer provided on at least one surface of the substrate of a recording medium, drying the pre-processing fluid, and forming an image on the recording medium by ejecting an aqueous ink thereon. The pre-processing fluid contains a hydrosoluble organic solvent, a flocculating agent formed of a quaternary salt of an adduct of alkyl amine.
    Type: Application
    Filed: December 17, 2014
    Publication date: June 25, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Michihiko Namba, Shosuke AOAI, Tsutomu MAEKAWA
  • Patent number: 8899719
    Abstract: An image forming method includes discharging an inkjet ink including a water-dispersible colorant, a wetter, a surfactant, a penetrant water-dispersible polyurethane resin having a median diameter of from 0.01 to 0.10 ?m water and at least one of a polyethylene wax and a paraffin wax on the surface of the recording medium on which the inkjet ink is discharged.
    Type: Grant
    Filed: November 7, 2013
    Date of Patent: December 2, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidefumi Nagashima, Michihiko Namba, Kiyofumi Nagai
  • Patent number: 8845091
    Abstract: A printing medium including at least base paper and a coating layer, wherein the coating layer is directly formed on the base paper by a cast coating method using a coating liquid, which contains kaolin and amorphous silica and contains the amorphous silica in an amount of 3% by mass to 20% by mass.
    Type: Grant
    Filed: March 17, 2010
    Date of Patent: September 30, 2014
    Assignees: Ricoh Company, Ltd., Hokuetsu Kishu Paper Co., Ltd.
    Inventors: Tohru Ohshima, Michihiko Namba, Kiyofumi Nagai, Atsushi Hasegawa, Shuichi Oguma, Hisanori Sakatsume
  • Publication number: 20140253631
    Abstract: A pre-treatment liquid includes a flocculant formed of a water-soluble cationic polymer obtained by copolymerizing an amine monomer and an epihalohydrin monomer; a surface conditioner; a surfactant; a water-soluble organic solvent; and water.
    Type: Application
    Filed: November 26, 2013
    Publication date: September 11, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Michihiko Namba, Shohsuke Aoai, Tsutomu Maekawa, Shinya Seno
  • Publication number: 20140192121
    Abstract: An inkjet recording method includes forming an image on a coated layer provided at least one side of the substrate of a recording medium with ink containing a colorant; and then applying a post-processing fluid comprising a resin to the image; wherein the application amount per unit area of the post-processing fluid to the image is controlled to be less than the application amount per unit area of the ink to form the image.
    Type: Application
    Filed: January 10, 2014
    Publication date: July 10, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Akiko Bannai, Hidefumi NAGASHIMA, Mariko KOJIMA, Michihiko NAMBA
  • Publication number: 20140192112
    Abstract: An image forming method includes discharging an inkjet ink including a water-dispersible colorant, a wetter, a surfactant, a penetrant water-dispersible polyurethane resin having a median diameter of from 0.01 to 0.10 ?m water and at least one of a polyethylene wax and a paraffin wax on the surface of the recording medium on which the inkjet ink is discharged.
    Type: Application
    Filed: November 7, 2013
    Publication date: July 10, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hidefumi NAGASHIMA, Michihiko Namba, Kiyofumi Nagai
  • Patent number: 8752948
    Abstract: An inkjet recording ink including a water-soluble organic solvent, a colorant, at least one fluorine-based surfactant having a chemical structure represented by Structural Formula (I) below, and water, where Rf represents any one of CF3, CF2CF3, (CF2)3F, and (CF2)4F, and X plus Y is an integer of 4 or 5.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: June 17, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Tamai, Michihiko Namba, Akihiko Matsuyama, Akihiko Gotoh, Kiyofumi Nagai
  • Patent number: 8727523
    Abstract: An inkjet recording ink including: a colorant; surfactant A; surfactant B; a water-soluble organic solvent; and water, wherein the surfactant A is represented by General Formula (1), and the surfactant B is at least one selected from compounds represented by General Formulas (2a) and (2b): where Rf represents CF3, CF2CF3, (CF2)3F or (CF2)4F, X and Y each are an integer of 1 or greater, and X+Y=4 or 5; where R3 and R4 each represent a hydrogen atom or a C1-20 alkyl group, r is a real number of 0 to 7, and s is a real number of 1 to 10, where each of R3 and R4 represents a hydrogen atom or a C1-20 alkyl group, t is a real number of 0 to 7, and u is a real number of 1 to 10.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: May 20, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Tamai, Michihiko Namba, Akihiko Matsuyama
  • Patent number: 8708473
    Abstract: Inkjet recording treatment liquids include: at least one water-soluble organic solvent; water; at least one compound according to formula (I) wherein: each of R1 and R3 independently represents H, a lower alkoxy group, or a lower perfluoroalkoxy group; each of R2 and R4 independently represents a lower perfluoroalkyl group; each of p, q, and r is independently an integer of 1 to 24; m is an integer of 1 to 28; and n is an integer of 0 to 10; and at least one compound according to formula (II) wherein: each of R5, R6, and R7 independently represents a lower alkyl group, a lower perfluoroalkoxy group, or F; and M is Li, Na, or K. Methods of inkjet recording, inkjet recording apparatus, storage bags, and cartridges employing the inkjet recording treatment liquids are also provided.
    Type: Grant
    Filed: June 17, 2011
    Date of Patent: April 29, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Michihiko Namba, Hidetoshi Fujii, Takashi Tamai, Akihiko Gotoh
  • Patent number: 8586647
    Abstract: The present invention provides a recording ink set containing a black ink, a cyan ink, a magenta ink, and a yellow ink, each of which contains water, a water-insoluble color material, a water-soluble organic solvent, and a surfactant, wherein the black ink and at least one of the inks other than the black ink respectively contain a different water-soluble organic solvent; and the surface tension of the water-soluble organic solvent(s) used only for the inks other than the black ink is higher than that of the water-soluble organic solvent used only for the black ink; and the present invention also provides a recording method using the recording ink set.
    Type: Grant
    Filed: October 24, 2006
    Date of Patent: November 19, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Mariko Kojima, Akihiko Gotoh, Michihiko Namba, Kiyofumi Nagai, Naoya Morohoshi, Tohru Ohshima
  • Patent number: 8580159
    Abstract: An ink for inkjet recording containing water, water-soluble organic solvent, water-dispersible resin, fluorochemical surfactant or derivative thereof, and coloring agent containing pigment, where the ink has a surface tension of 20-35 mN/m and viscosity of ?5 mPa·s at 25° C., total amount of the water-dispersible resin and the coloring agent in the ink is 5-40% by mass, and mass ratio A/B of the water-dispersible resin A to the coloring agent B is 0.5-4, where the ink is applied to a recording medium containing a support containing cellulose pulp, and one or more barrier layers disposed on a face of the support, and where the barrier layer contains ?30% by mass of inorganic pigment having refractive index of ?1.5, excluding aluminum hydrate, and ?10% by mass of inorganic pigment having a refractive index of <1.5.
    Type: Grant
    Filed: July 10, 2012
    Date of Patent: November 12, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Michihiko Namba, Akihiko Matsuyama, Naoya Morohoshi, Tohru Ohshima, Masayuki Koyano, Akihiko Gotoh, Kiyofumi Nagai
  • Patent number: 8556405
    Abstract: There is provided an ink for recording, which contains: a coloring agent; a water-dispersible resin; a wetting agent; a surfactant; and water, wherein a total solid content of the coloring agent and the water-dispersible resin is 10% by mass to 30% with respect to a total mass of the ink, a ratio B/C is 0.1 to 1.6 where B is a solid content of the coloring agent in the ink, and C is a solid content of the water-dispersible resin in the ink, a viscosity of the ink is 5 mPa·s to 20 mPa·s at 25° C., and a surface tension of the ink is 35 mN/m or less.
    Type: Grant
    Filed: August 22, 2011
    Date of Patent: October 15, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Hisashi Habashi, Michihiko Namba, Mariko Kojima, Akihiko Gotoh, Tamotsu Aruga, Kiyofumi Nagai
  • Publication number: 20130201252
    Abstract: A post-treatment liquid for inkjet recording including a urethane resin, a fluorosurfactant, a water-soluble organic solvent and water.
    Type: Application
    Filed: January 17, 2013
    Publication date: August 8, 2013
    Inventor: Michihiko NAMBA
  • Publication number: 20130194345
    Abstract: A cleaning filling liquid for inkjet device comprising: Water; 10.0% by mass to 45% by mass per whole amount of the cleaning filling liquid of an amide compound having following structural formula (1).
    Type: Application
    Filed: January 31, 2013
    Publication date: August 1, 2013
    Inventors: Takashi TAMAI, Tomohiro Inoue, Hiroshi Gotou, Michihiko Namba, Akihiko Gotoh, Kiyofumi Nagai
  • Patent number: 8444755
    Abstract: An ink-jet recording ink including water, a water-soluble organic solvent, a pigment as a colorant (B), and at least one fluorochemical surfactant selected from compounds represented by Structural Formula (1) below, Structural Formula (1) where R1 denotes any one of a hydrogen atom, an alkyl group and a perfluoroalkyl group, R2 denotes any one of a hydrogen atom, an alkyl group and a fluorine-containing group, Rf denotes a fluorine-containing group, and m and n each denote an integer of 1 or greater.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: May 21, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Michihiko Namba, Naoya Morohoshi, Tohru Ohshima, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20130113860
    Abstract: To provide an inkjet ink, which contains: water; a wetting agent; a surfactant; and a colorant, wherein the wetting agent contains at least an amide compound represented by the following structural formula (I):
    Type: Application
    Filed: July 29, 2011
    Publication date: May 9, 2013
    Inventors: Hiroshi Gotou, Kiyofumi Nagai, Michihiko Namba, Hidetoshi Fujii, Yuuki Yokohama