Patents by Inventor Kiyofumi Nagai

Kiyofumi Nagai 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: 7938527
    Abstract: To provide an ink jet recording method including: performing image recording on a recording medium to obtain an ink adhesion quantity of 15 g/m2 or less of an ink containing at least a colorant, the recording medium having at least one coating layer on at least one surface of a substrate including cellulose pulp; and dry-to-touch drying the recorded image and bringing a heat source into direct contact with the recording medium for image fixing, wherein the recording medium is formed such that a transfer quantity of pure water into the recording medium in a contact interval of 100 ms that is measured with a dynamic scanning liquid absorptometer is 1 mL/m2 or more to 30 mL/m2 or less and a transfer quantity of pure water into the recording medium in a contact interval of 400 ms is 2 mL/m2 or more to 35 mL/m2 or less.
    Type: Grant
    Filed: September 18, 2007
    Date of Patent: May 10, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Tohru Ohshima, Naoya Morohoshi, Kiyofumi Nagai, Hiroyuki Kiyoi, Masanori Hirano, Shigetaka Sakakibara
  • Patent number: 7922316
    Abstract: An inkjet recording apparatus is provided, wherein the inkjet recording apparatus contains a recording head with a filter, an ink that comprises a colorant, a humectant, a surfactant, and a wetting agent is discharged from the recording head, the viscosity of the ink at 25° C. is 6 mPas to 13 mPas, and the fluid resistance of the filter against the ink is 4.4×109 Pas/m3 and 2.2×1010 Pas/m3.
    Type: Grant
    Filed: October 26, 2005
    Date of Patent: April 12, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Akiko Bannai, Eisuke Hori, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20110057981
    Abstract: A recording ink containing at least a solid component which contains a colorant and a resin and is a solid at 25° C., a liquid component which has a higher boiling point than that of water and is a liquid at 25° C. and water, wherein the total content of the liquid component in the recording ink is 20% by mass or less, the total content of the solid component in the recording ink is 20% by mass or more, and the total content of a resin component in the solid component is 40% by mass to 95% by mass relative to a total amount of the solid component is provided.
    Type: Application
    Filed: August 5, 2010
    Publication date: March 10, 2011
    Inventors: Tamotsu Aruga, Masayuki Koyano, Akihiko Matsuyama, Hisashi Habashi, Hiroshi Goto, Tohru Ohshima, Naoya Morohoshi, Kiyofumi Nagai
  • Patent number: 7892340
    Abstract: An ink-jet recording ink including water, a water-soluble organic solvent, a pigment (P1) as a colorant (B), and at least one fluorochemical surfactant selected from compounds represented by Structural Formula (1) below, where R1 denotes any one of a hydrogen atom, an alkyl group and a fluorine-containing group, Rf denotes a fluorine-containing group, and each of x, y and z denotes an integer of 1 or greater.
    Type: Grant
    Filed: November 20, 2008
    Date of Patent: February 22, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Michihiko Namba, Naoya Morohoshi, Tohru Ohshima, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20100295891
    Abstract: An image forming method of the present invention including applying a pretreatment liquid to a recording medium, and discharging an inkjet recording ink dropwise according to an image signal to form an image on the recording medium on which the pretreatment liquid has been applied, wherein the recording medium is regular paper which has no coat layer, the pretreatment liquid contains a cationic polymer compound, a surfactant A, water and a water-soluble organic acid, and the inkjet recording ink contains a water-dispersible colorant, a water-soluble organic solvent, a surfactant B, a penetrating agent and water, and wherein the pretreatment liquid has a static surface tension of 20 mN/m to 30 mN/m.
    Type: Application
    Filed: January 16, 2009
    Publication date: November 25, 2010
    Inventors: Hiroshi Goto, Hisashi Habashi, Kiyofumi Nagai
  • Publication number: 20100279035
    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: Application
    Filed: December 18, 2008
    Publication date: November 4, 2010
    Inventors: Michihiko Namba, Naoya Morohoshi, Tohru Ohshima, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20100277541
    Abstract: An ink jet recording medium having an ink receiving layer containing a binder which containing an acrylonitrile butadiene type copolymer, the butadiene concentration of the copolymer is 50 weight % or more, and an inorganic pigment on one or two sides of a base paper mainly composed of wood pulp, wherein the concentration ratio of the acrylonitrile butadiene type copolymer to 100 parts by weight of the inorganic pigment is from one part by weight to eight parts by weight, while 60 weight % or more of the inorganic pigment is kaolin with particles of 0.4 ?m or more and below 4.2 ?m which account for 64% or more as the cumulative value of the volumetric basis when measured using a laser diffraction method, and the surface roughness of the ink receiving layer is from 0.6 ?m to 1.4 ?m when a hard backing is used at a clamp pressure of 1,000 kPa according to JIS P8151.
    Type: Application
    Filed: October 30, 2008
    Publication date: November 4, 2010
    Applicants: NIPPON PAPER INDUSTRIES CO., LTD., RICOH COMPANY, LTD.
    Inventors: Taichi Watanabe, Yuji Sawa, Kei Takigawa, Naoya Morohoshi, Kiyofumi Nagai
  • Publication number: 20100271435
    Abstract: The object of the invention to provide a recording ink with excellent discharge stability and storage stability, which rapidly penetrates into a recording medium and forms a coating, and which will never generate smearing upon high-speed printing or double-sided printing, and which excels in marker resistance, and which enables high quality image recording with less bleeding, and the ink cartridge, the ink record, the inkjet recording apparatus, and the inkjet recording method using the recording ink.
    Type: Application
    Filed: July 7, 2010
    Publication date: October 28, 2010
    Inventors: Mariko KOJIMA, Tomohiro Inoue, Akihiko Gotoh, Michihiko Namba, Hisashi Habashi, Akiko Bannai, Kiyofumi Nagai
  • Publication number: 20100265292
    Abstract: To provide an ink jet recording method including: performing image recording on a recording medium to obtain an ink adhesion quantity of 15 g/m2 or less of an ink containing at least a colorant, the recording medium having at least one coating layer on at least one surface of a substrate including cellulose pulp; and dry-to-touch drying the recorded image and bringing a heat source into direct contact with the recording medium for image fixing, wherein the recording medium is formed such that a transfer quantity of pure water into the recording medium in a contact interval of 100 ms that is measured with a dynamic scanning liquid absorptometer is 1 mL/m2 or more to 30 mL/m2 or less and a transfer quantity of pure water into the recording medium in a contact interval of 400 ms is 2 mL/m2 or more to 35 mL/m2 or less.
    Type: Application
    Filed: September 18, 2007
    Publication date: October 21, 2010
    Inventors: Tohru Ohshima, Naoya Morohoshi, Kiyofumi Nagai, Hiroyuki Kiyoi, Masanori Hirano, Shigetaka Sakakibara
  • Patent number: 7812068
    Abstract: The invention provides a recording ink containing a colorant, a wetting agent, a surfactant, a penetrating agent, and water, wherein when the specified moisture evaporation rate of the recording ink is less than 30% the specified viscosity elevating rate of the recording ink is 10 or less; when the moisture evaporation rate is 30% to 50%, there is a point at which the viscosity elevating rate is more than 500; and when the moisture evaporation rate is less than 30%, the average particle diameter of the colorant in the recording ink is two times or less the initial average particle diameter of the colorant before the moisture evaporation test of the recording ink.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: October 12, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Hisashi Habashi, Kiyofumi Nagai, Akiko Bannai
  • Patent number: 7810919
    Abstract: The object of the invention to provide a recording ink with excellent discharge stability and storage stability, which rapidly penetrates into a recording medium and forms a coating, and which will never generate smearing upon high-speed printing or double-sided printing, and which excels in marker resistance, and which enables high quality image recording with less bleeding, and the ink cartridge, the ink record, the inkjet recording apparatus, and the inkjet recording method using the recording ink. The recording ink containing at least water, a colorant, a resin fine-particle, a water-soluble organic solvent and a penetrant, in which the penetrant is a diol compound whose carbon number is 7 to 11 and the resin fine-particle is a silicone modified acrylic resin not containing a hydrolyzable silyl group.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: October 12, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Mariko Kojima, Tomohiro Inoue, Akihiko Gotoh, Michihiko Namba, Hisashi Habashi, Akiko Bannai, Kiyofumi Nagai
  • Publication number: 20100245416
    Abstract: An ink-jet recording method including: printing on a medium by ejecting thereon ink having a pH value of 8 or more and containing at least a particulate colorant, emulsion resin and surfactant, the medium prepared by providing at least a coat layer containing a pigment on at least one surface of a substrate containing cellulose pulp as a main component, wherein printing is performed at a deposited ink amount of 15 g/m2 or less, and wherein the medium has a pH value of 8 or more at a paper surface, and the amount of pure water transferring onto a surface of the medium having the coat layer after a contact time of 100 ms measured with a dynamic scanning absorptometer is 30 mL/m2 or less and the amount of pure water transferring onto the surface of the medium after a contact time of 400 ms is 35 mL/m2 or less.
    Type: Application
    Filed: March 17, 2008
    Publication date: September 30, 2010
    Inventors: Tohru Ohshima, Kiyofumi Nagai, Naoya Morohoshi, Michihiko Namba
  • Publication number: 20100215855
    Abstract: The present invention provides an ink-media set, record printed by use of the ink-media set, an inkjet printing method, and an inkjet printing apparatus which includes ink that has at least water, dye, and humectant and surface tension thereof is 20 to 35 mN/m at 25° C., a support, and a recording medium having the support and at least one surface thereof has a coating layer wherein transfer rate of the ink to the recording medium measured by a dynamic scanning absorptometer in 100 ms of contact time is 4 to 15 ml/m2 and transfer rate of the ink to the recording medium measured by a dynamic scanning absorptometer in 400 ms of contact time is 7 to 20 ml/m2.
    Type: Application
    Filed: March 3, 2010
    Publication date: August 26, 2010
    Inventors: Naoya Morohoshi, Tohru Ohshima, Kiyofumi Nagai
  • Publication number: 20100196602
    Abstract: An ink set includes at least two aqueous inks A and B with different colors, the inks A and B used in an inkjet recording method in which the inks A and B are superimposed for formation of a color image, wherein the ink A contains water-dispersible colorant A1 free of a surfactant-based dispersant, and anionic compound A2, and wherein the ink B contains water-dispersible colorant B1 containing a surfactant-based dispersant.
    Type: Application
    Filed: September 18, 2008
    Publication date: August 5, 2010
    Inventors: Masayuki Koyano, Hiroshi Goto, Tamotsu Aruga, Kiyofumi Nagai, Toshiroh Tokuno
  • Publication number: 20100194837
    Abstract: The image recording method includes ejecting an ink to form an image on the surface of a recording layer of a recording medium; and then applying a glossiness imparting liquid on the surface of the recording medium. The ink includes a particulate colorant, a surfactant and water, and has a solid content of not lower than 6% by weight. The recording layer is located overlying a substrate including cellulose pulp as a main component and includes an inorganic pigment and a styrene-butadiene copolymer. The surface of the recording medium bearing the recording layer absorbs the ink in an amount of from 1 ml/m2 to 10 ml/m2 before coating the glossiness imparting liquid when the ink absorbing amount is measured with a dynamic scanning absorptometer at a contact time of 500 ms.
    Type: Application
    Filed: January 7, 2010
    Publication date: August 5, 2010
    Inventors: Tohru OHSHIMA, Kiyofumi NAGAI
  • Publication number: 20100196603
    Abstract: An inkjet medium having a support mainly containing a cellulose pulp, and a coat layer containing a pigment and an adhesive, the coat layer formed on at least one surface of the support, wherein the pigment in the coat layer as an outermost layer contains at least light calcium carbonate, kaolin and gel type silica, and has an average oil absorption of 70 ml/100 g to 120 ml/100 g.
    Type: Application
    Filed: August 29, 2008
    Publication date: August 5, 2010
    Inventors: Tohru Ohshima, Kiyofumi Nagai, Yuuji Kojima, Yasuharu Onogi
  • Publication number: 20100196601
    Abstract: An ink-jet recording ink including a colorant dispersible in water, a water-soluble organic solvent used as a wetting agent, a surfactant, a penetrant, a water-dispersible resin, and water, wherein when 2.5 g of the ink is weighed, placed in a glass Petri dish having a diameter of 33 mm and stored for 24 hr at a temperature of 50° C.±0.5° C. and a humidity of 12%±5%, the evaporation rate of a solvent (water+water-soluble organic solvent) in the ink is 50% by weight or more, and an ink residue has a viscosity of 20,000 mPa-S or greater, and wherein by storing the ink residue for 6 hr at a temperature of 23° C.±0.5° C. and a high humidity of 95%±3% to allow it to absorb moisture, the amount of moisture contained in the ink residue becomes 30% by weight to 40% by weight, in which case the ink residue has a viscosity of less than 500 mPa s.
    Type: Application
    Filed: June 12, 2008
    Publication date: August 5, 2010
    Inventors: Hiroshi Goto, Kiyofumi Nagai, Tamotsu Aruga, Masayuki Koyano
  • Publication number: 20100196673
    Abstract: An ink-jet recording method including recording onto a recording medium a black image of composite black using a black ink and color inks, wherein the black ink includes water, a water-soluble organic solvent, a surfactant, and a carbon black whose volume average particle diameter is 40 nm to 100 nm, and the color inks include a cyan ink, a magenta ink and a yellow ink, wherein the mass ratio (A/B) of a solid content A to a water-soluble organic solvent content B in the black ink is in the range of 1/8 to 1/15, and wherein the recording medium includes a support with a coating layer, and the amounts of purified water transferred to the recording medium at contact periods of 100 ms and 400 ms at a temperature of 23 C and a relative humidity of 50% are 2 ml/m2 to 35 ml/m2 and 3 ml/m2 to 40 ml/m2 respectively.
    Type: Application
    Filed: June 26, 2008
    Publication date: August 5, 2010
    Inventors: Hidefumi Nagashima, Kiyofumi Nagai
  • Patent number: 7699457
    Abstract: The recording ink having a water, a water-soluble organic solvent, a colorant, and at least one fluorochemical surfactant selected from the following Structural Formulae (1) to (3). Structural Formula (1): where, Rf is a fluorine-containing group; and m, n, and p are integers in the Structural Formula (1). Structural Formula (2): where, Rf is a fluorine-containing group; X is a cationic group; Y is an anionic group; and q is an integer in the Structural Formula (2). Structural Formula (3): where, Rf is a fluorine-containing group; X is a cationic group; Y is an anionic group; and q is an integer in the Structural Formula (3).
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: April 20, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Michihiko Namba, Hisashi Habashi, Akihiko Gotoh, Kiyofumi Nagai, Tomohiro Inoue
  • Patent number: 7682011
    Abstract: The object of the present invention is to provide a recording ink which is excellent in color developing properties, has a high delivery stability, can improve remarkably color saturation and can form a high-quality image, when the ink is used for printing a plain paper, further an ink cartridge, an ink record, an inkjet recording apparatus and an inkjet recording process, wherein the recording ink having water, a wetting agent, a surfactant, and a colorant.
    Type: Grant
    Filed: January 10, 2007
    Date of Patent: March 23, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Michihiko Namba, Hisashi Habashi, Mariko Kojima, Tomohiro Inoue, Akiko Bannai, Akihiko Gotoh, Kiyofumi Nagai