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).

  • Publication number: 20090291213
    Abstract: To provide an inkjet recording method including: flying ink by application of stimulation to the ink to form an image on a recording media, wherein the recording media has at least one barrier layer of 10 m or less in thickness on at least one surface of a substrate comprising a cellulose pulp, the barrier layer contains 30% by mass or more of an inorganic pigment with a refraction index of 1.5 or less other than alumina, and the content of pigment with a refraction index of less than 1.5 in the barrier layer is 10% by mass or less, wherein the ink contains either a pigment or colored fine particle as coloring material, and a coloring material fixing constituent, and the surface tension of the ink is 25 mN/m or less, and the total amount of the ink on the recording media is 15 g/m2 or less.
    Type: Application
    Filed: October 26, 2006
    Publication date: November 26, 2009
    Inventors: Tohru Ohshima, Naoya Morohoshi, Kiyofumi Nagai
  • Publication number: 20090263632
    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: Application
    Filed: October 24, 2006
    Publication date: October 22, 2009
    Inventors: Mariko Kojima, Akihiko Gotoh, Michihiko Namba, Kiyofumi Nagai, Naoya Morohoshi, Tohru Ohshima
  • Publication number: 20090258196
    Abstract: There is provided an inkjet recording ink and recording media set, which contains: an inkjet recording ink; and a recording medium, wherein the inkjet recording ink comprises at least: water; a water-soluble organic solvent; and a colorant containing carbon black, and having a volume average particle diameter of 40 nm to 100 nm, wherein the recording medium contains: a substrate; and a coating layer on at least one side of the substrate, and wherein an amount of pure water transferred to the recording medium, as measured with a dynamic scanning absorptometer at 23 C and 50% RH, at a contact time of 100 ms is 2 ml/m2 to 35 ml/m2 while an amount of pure water transferred to the recording medium at a contact time of 400 ms is 3 ml/m2 to 40 ml/m2.
    Type: Application
    Filed: March 14, 2008
    Publication date: October 15, 2009
    Inventors: Hidefumi Nagashima, Kiyofumi Nagai, Michihiko Namba, Mariko Kojima
  • Publication number: 20090239044
    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: Application
    Filed: August 22, 2006
    Publication date: September 24, 2009
    Inventors: Hisashi Habashi, Michihiko Namba, Mariko Kojima, Akihiko Gotoh, Tamotsu Aruga, Kiyofumi Nagai
  • Publication number: 20090186162
    Abstract: To provide an ink for inkjet recording containing water, water-soluble organic solvent, water-dispersible resin, fluorochemical surfactant or derivative thereof, and coloring agent containing pigment, wherein the ink has a surface tension of 20-35 mN/m and viscosity of 5 mPa·s or more 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, wherein the ink is applied for a recording medium for inkjet recording containing a support containing cellulose pulp, and one or more barrier layers disposed on at least one face of the support, and wherein the barrier layer contains 30% by mass or more of inorganic pigment having refractive index of 1.5 or more, excluding aluminum hydrate, and 10% by mass or less of inorganic pigment having a refractive index of less than 1.5.
    Type: Application
    Filed: August 30, 2007
    Publication date: July 23, 2009
    Inventors: Michihiko Namba, Akihiko Matsuyama, Naoya Morohoshi, Tohru Ohshima, Masayuki Koyano, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20090176070
    Abstract: A pigment dispersion is provided that includes a pigment, a pigment dispersant, a polymer dispersion stabilizer and water, wherein the polymer dispersion stabilizer is an alpha-olefin/maleic anhydride copolymer expressed by the formula (1) below. A recording ink is also provided that includes the pigment dispersion, a surfactant, a water-dispersible resin, a humectant and water. In the structural formula (1), R represents an alkyl group and n is an integer of 30 to 100.
    Type: Application
    Filed: December 15, 2006
    Publication date: July 9, 2009
    Inventors: Hiroshi Goto, Akihiko Matsuyama, Kiyofumi Nagai
  • Publication number: 20090162569
    Abstract: There is provided a recording ink containing: solid constituents, which contain a colorant and a resin, and stay solid in the ink having a temperature of 25° C.; liquid constituents, which have a higher boiling point than a boiling point of water, and stay liquid in the ink having a temperature of 25° C.; and water, wherein a total amount of the solid constituents in the recording ink is in the range of 2.0% by mass or more to less than 20% by mass, wherein a ratio A/B of a total amount of the liquid constituents in the recording ink A to the total amount of the solid constituents in the recording ink B is from 0.70 to 1.75, and wherein the viscosity of the recording ink at 25° C. is 10 mPa s or less.
    Type: Application
    Filed: September 12, 2007
    Publication date: June 25, 2009
    Inventors: Naoya Morohoshi, Tamotsu Aruga, Michihiko Namba, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20090130313
    Abstract: To provide an ideal inkjet recording method capable of full-color printing and of inexpensively providing prints that have a texture similar to those of commercial prints and that offer excellent print quality, image density, image fidelity and smear resistance, by combining a specific recording media and a specific pigment-based inkjet ink. The inkjet recording method uses an ink containing particulate coloring material for printing on a media that includes a substrate composed primarily of cellulose pulp and one or more coated layers formed on at least one surface of the substrate, wherein the media has an air permeability of 0.1 ml/min to 30 ml/min as measured using a Parker Print-Surf.
    Type: Application
    Filed: April 18, 2007
    Publication date: May 21, 2009
    Inventors: Tohru Ohshima, Naoya Morohoshi, Kiyofumi Nagai
  • Publication number: 20090098312
    Abstract: The present invention provides a recording ink including a composite pigment particle, a water-soluble solvent, and water, wherein the composite pigment particle is a primary particle coated with a coating resin, wherein the primary particle is a white pigment on the surface of which an oil-soluble dye is adsorbed or attached. In one aspect, the white pigment is preferably at least one selected from a white inorganic pigment, a pearl pigment, and an extender pigment, in another aspect, the coating resin is preferably one of a (meth)acrylic resin, a polyester resin, and a polyurethane resin, wherein the acid value of the coating resin is from 50 mgKOH/g to 250 mgKOH/g, and in another aspect, an average particle diameter (D50%) of the composite pigment particle is preferably 150 nm or less.
    Type: Application
    Filed: March 9, 2007
    Publication date: April 16, 2009
    Inventors: Hiroshi Goto, Akihiko Matsuyama, Kiyofumi Nagai
  • Publication number: 20080302268
    Abstract: An ink for ink jet recording which is used for an ink jet printer in which at least a portion of a member being in contact with the ink is formed by any one of a borosilicate glass, a soda lime glass, a photosensitive glass, single crystal silicon, polysilicon, a silicon oxide film, a titanium nitride film, a zirconium film, a titanium oxide film, and a silicon nitride film, wherein a corrosion inhibitor is contained, and a phosphonium ion represented by the general formula (Formula 1) described below is contained: (wherein in Formula 1, Ra, Rb, Rc and Rd represent a linear, branched, or cyclic alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group, a halogenated alkyl group and a substituted or non substituted phenyl group, and X? represents a counter ion) is provided.
    Type: Application
    Filed: April 7, 2008
    Publication date: December 11, 2008
    Inventors: Hitoshi ARITA, Nobutaka Osada, Kiyofumi Nagai, Kakuji Murakami, Akihiko Gotoh
  • Publication number: 20080273045
    Abstract: An ink-jet recording process which conducts recording by imparting ink onto the surface of a recording medium according to recording information, where the recording medium has a base material and a porous ink receiving layer thereon containing inorganic particles having a BET specific surface area of at least 150 m2/g, and the ink contains a polymer emulsion having a water-insoluble or hardly-soluble colorant contained in polymer fine particles and at least one wetting agent, 8-11 C polyol or glycol ether, anionic or nonionic surfactant, water-soluble organic solvent, and water; and has a surface tension of 40 mN/m or less at 25° C. This process can provide high-grade images excellent in ink absorbing and fixing properties and satisfactory in color tone, produce images excellent in image fastness such as water resistance and light resistance, and implement ink-jet recording excellent in storage stability and discharge stability and free from head clogging at printing.
    Type: Application
    Filed: September 20, 2002
    Publication date: November 6, 2008
    Inventors: Naoya Morohoshi, Masayuki Koyano, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20080254228
    Abstract: There is provided a recording ink containing at least: water; a water-soluble organic solvent; a surfactant; and a carbon black having a hydrophilic group on a surface thereof, wherein the carbon black releases humic acid in an aqueous dispersion of the carbon black, which is recovered from the recording ink, a concentration of the humic acid released in the aqueous dispersion containing 20% by mass of the carbon black of is expressed with a maximum absorbance at a wavelength of 230 nm to 260 nm, and the recording ink has the maximum absorbance of 5.0 to 20.0 at the wavelength of 230 nm to 260 nm.
    Type: Application
    Filed: September 12, 2007
    Publication date: October 16, 2008
    Inventors: Mariko Kojima, Kiyofumi Nagai, Akihiko Gotoh, Akiko Bannai, Tomohiro Inoue
  • Publication number: 20080248260
    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: Application
    Filed: September 16, 2005
    Publication date: October 9, 2008
    Applicant: RICOH COMPANY, LTD.
    Inventors: Mariko Kojima, Tomohiro Inoue, Akihiko Gotoh, Michihiko Namba, Hisashi Habashi, Akiko Bannai, Kiyofumi Nagai
  • Publication number: 20080138519
    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: Application
    Filed: August 4, 2005
    Publication date: June 12, 2008
    Applicant: RICOH COMPANY, LTD
    Inventors: Hisashi Habashi, Kiyofumi Nagai, Akiko Bannai
  • Patent number: 7374608
    Abstract: An ink for ink jet recording which is used for an ink jet printer in which at least a portion of a member being in contact with the ink is formed by any one of a borosilicate glass, a soda lime glass, a photosensitive glass, single crystal silicon, polysilicon, a silicon oxide film, a titanium nitride film, a zirconium film, a titanium oxide film, and a silicon nitride film, wherein a corrosion inhibitor is contained, and a phosphonium ion represented by the general formula (Formula 1) described below is contained: (wherein in Formula 1, Ra, Rb, Rc and Rd represent a linear, branched, or cyclic alkyl group having 1 to 4 carbon atoms, a hydroxyalkyl group, a halogenated alkyl group and a substituted or non substituted phenyl group, and X? represents a counter ion) is provided.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: May 20, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Hitoshi Arita, Nobutaka Osada, Kiyofumi Nagai, Kakuji Murakami, Akihiko Gotoh
  • Patent number: 7370952
    Abstract: A water-based ink containing a surface treated pigment as a coloring material, a water-soluble organic solvent, water, both for dispersing the pigment, an organic pH buffer selected from Good's buffers, and a compound selected from aminopropanediol derivatives. This water-based ink has a high storage stability which exhibits reduced change in pH, in particular, reduced decrease of pH during the storage. Due to this, it is possible to provide a highly durable inkjet recording apparatus wherein dissolution of the member constituting the printer system that comes in contact with the ink is prevented, and a recording process.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: May 13, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomohiro Inoue, Kiyofumi Nagai
  • Publication number: 20080094458
    Abstract: An inkjet recording apparatus is provided, wherein the inkjet recording apparatus comprises 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 mPa·s to 13 mPa·s, and the fluid resistance of the filter against the ink is 4.4×109 Pa·s/m3 and 2.2×1010 Pa·s/m3.
    Type: Application
    Filed: October 26, 2005
    Publication date: April 24, 2008
    Inventors: Akiko Bannai, Eisuke Hori, Akihiko Gotoh, Kiyofumi Nagai
  • Publication number: 20080070008
    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: Application
    Filed: September 13, 2005
    Publication date: March 20, 2008
    Inventors: Michihiko Namba, Hisashi Habashi, Akihiko Gotoh, Kiyofumi Nagai, Tomohiro Inoue
  • Patent number: 7284851
    Abstract: A recording ink including a colorant dispersible in water, a humectant, a surfactant, and a wetting agent, wherein the rate of viscosity increase associated with evaporation of moisture in the recording ink is 5.0 mPa·s/% or less while the evaporated moisture content is less than 30% by weight based on the whole weight of the recording ink, the rate of viscosity increase associated with evaporation of moisture exceeds 50 mPa·s/% while the evaporated moisture content is 30 to 45% by weight, and the average particle size of the colorant in the recording ink is less than five times the average particle size of the colorant in the initial recording ink, and is 0.8 ?m or less, at the stage of the recording ink when the rate of viscosity increase amounts to 50 mPa·s/%, wherein the rate of viscosity increase associated with evaporation of moisture (mPa·s/%) is defined as the increment of viscosity (mPa·s) versus the increment of evaporated moisture content (%).
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: October 23, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Akiko Bannai, Kiyofumi Nagai, Akihiko Gotoh, Mariko Kojima, Michihiko Namba, Tomohiro Inoue
  • Patent number: 7278726
    Abstract: Disclosed is an ink set for use in an ink jet recording process, wherein at least two aqueous inks A and B having different hues are superimposed to form a color image. The ink set can give a clear color image by high speed printing having good resolution without bleeding in the boundaries between two colors. Disclosed also are a method, an ink cartridge and an apparatus for ink jet recording using the above ink set. The ink set is characterized in that, of the two aqueous inks A and B, one ink A includes a coloring material A having an anionic group and in that the other ink B includes a coloring material B and a quaternary ammonium salt having at least one alkyl group which has 6 or less carbon atoms and which has a hydroxyl group.
    Type: Grant
    Filed: June 19, 2002
    Date of Patent: October 9, 2007
    Assignee: Ricoh Company, Ltd.
    Inventor: Kiyofumi Nagai