Patents by Inventor Mio KUMAI

Mio KUMAI 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: 11168228
    Abstract: An ink contains a water-soluble organic solvent, a glittery pigment having a median size less than 300 nm, and a polycarbonate-based urethane resin.
    Type: Grant
    Filed: March 27, 2019
    Date of Patent: November 9, 2021
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hidefumi Nagashima, Mio Kumai, Yuri Haga
  • Patent number: 10807378
    Abstract: An ink set comprises black ink having a static surface tension A and yellow ink having a static surface tension B, wherein the static surface tension A is 28.7 mN/m or more and greater than the static surface tension B, wherein the ink set is used in an image forming device including an inkjet head including a nozzle plate including a first nozzle array and a second nozzle array disposed adjacent to the first nozzle array, the first nozzle array including multiple first nozzles configured to discharge the black ink and a second nozzle array including multiple second nozzles configured to discharge the yellow ink wherein each nozzle of the multiple first nozzles and the multiple second nozzles has a cylindrical portion having a length of 25 ?m or longer along an axial direction with an opening on an ink discharging side of the nozzle plate.
    Type: Grant
    Filed: March 6, 2019
    Date of Patent: October 20, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Watanabe, Taku Hatakeyama, Kaoru Tadokoro, Sho Oyamatsu, Tomohiro Inoue, Hiroshi Gotou, Mio Kumai
  • Patent number: 10696069
    Abstract: A liquid discharge apparatus includes a conveyance path, a liquid discharge head, and a drying device. A medium is to be conveyed on the conveyance path. The liquid discharge head discharges liquid onto the medium conveyed on the conveyance path. The conveyance path includes a switchback path and an ejection path. The switchback path switches back a conveyance direction of the medium onto which the liquid has been discharged. The ejection path conveys the medium onto which the liquid has been discharged to an ejection port. The drying device dries the medium both on the switchback path and on the ejection path.
    Type: Grant
    Filed: March 6, 2019
    Date of Patent: June 30, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Hatakeyama, Takashi Watanabe, Kaoru Tadokoro, Sho Oyamatsu, Tomohiro Inoue, Hiroshi Gotou, Mio Kumai
  • Patent number: 10654292
    Abstract: A liquid discharge apparatus includes a conveyance path, a liquid discharge head, an ejection tray, and a drying device. A medium is conveyed in the conveyance path. The liquid discharge head discharges liquid onto the medium conveyed in the conveyance path. The medium is ejected to the ejection tray. The drying device dries the medium. The conveyance path includes a first bending portion to bend the medium, with a liquid-applied surface of the medium facing inward. The ejection tray includes a second bending portion to bend the medium, with the liquid-applied surface of the medium facing inward. A curvature of the medium bent by the first bending portion is greater than a curvature of the medium bent by the second bending portion. The drying device dries the medium conveyed in the first bending portion.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: May 19, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Hatakeyama, Takashi Watanabe, Kaoru Tadokoro, Sho Oyamatsu, Tomohiro Inoue, Hiroshi Gotou, Mio Kumai
  • Patent number: 10618331
    Abstract: An ink set comprises black ink having a static surface tension A and yellow ink having a static surface tension B, wherein the static surface tension A is by 0.6 mN/m or more greater than the static surface tension B, wherein the ink set is used in an image forming device including an inkjet head including a nozzle plate including a first nozzle array and a second nozzle array disposed adjacent to the first nozzle array, the first nozzle array including multiple first nozzles configured to discharge the black ink and a second nozzle array including multiple second nozzles configured to discharge the yellow ink, wherein each nozzle of the multiple first nozzles and the multiple second nozzles has a cylindrical portion having a length of 25 ?m or longer along an axial direction with an opening on an ink discharging side of the nozzle plate.
    Type: Grant
    Filed: March 6, 2019
    Date of Patent: April 14, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Watanabe, Taku Hatakeyama, Kaoru Tadokoro, Sho Oyamatsu, Tomohiro Inoue, Hiroshi Gotou, Mio Kumai
  • Publication number: 20200095437
    Abstract: To provide an active-energy-ray-curable composition including a resin, where a ratio S3/S30 of the active-energy-ray-curable composition is 0.3 or more but 0.6 or less in a 1H-NMR spectrum of the active-energy-ray-curable composition, the 1H-NMR spectrum is obtained when a concentration of the active-energy-ray-curable composition in deuterated chloroform as a solvent is 3% by mass, the S30 is an integrated value of all signals in the 1H-NMR spectrum, and the S3 is an integrated value of at least one broad signal in the 1H-NMR spectrum.
    Type: Application
    Filed: December 20, 2017
    Publication date: March 26, 2020
    Inventors: Yuri HAGA, Mio KUMAI, Hidefumi NAGASHIMA, Maiko KOEDA
  • Patent number: 10508211
    Abstract: An ink includes water, a coloring material, an organic solvent having a solubility parameter of from 8.0 to 13.0, an urethane resin particle and a metal ion, wherein the organic solvent having the solubility parameter of from 8.0 to 13.0 has a proportion of from 10.0% by mass to 30.0% by mass to the ink, where the metal ion is at least one selected from an alkali metal ion and an alkaline earth metal ion, where the metal ion has a proportion of from 4000 mg/L to 8000 mg/L to the ink.
    Type: Grant
    Filed: September 14, 2018
    Date of Patent: December 17, 2019
    Assignee: RICOH COMPANY, LTD.
    Inventors: Azumi Miyaake, Kaori Miyahara, Masayuki Koyano, Mio Kumai, Ayano Momose, Satoshi Kojima, Kiminori Masuda, Amika Sagara, Hiroki Hagiwara
  • Publication number: 20190300731
    Abstract: An ink contains a water-soluble organic solvent, a glittery pigment having a median size less than 300 nm, and a polycarbonate-based urethane resin.
    Type: Application
    Filed: March 27, 2019
    Publication date: October 3, 2019
    Inventors: Hidefumi NAGASHIMA, Mio KUMAI, Yuri HAGA
  • Publication number: 20190283460
    Abstract: A liquid discharge apparatus includes a conveyance path, a liquid discharge head, an ejection tray, and a drying device. A medium is conveyed in the conveyance path. The liquid discharge head discharges liquid onto the medium conveyed in the conveyance path. The medium is ejected to the ejection tray. The drying device dries the medium. The conveyance path includes a first bending portion to bend the medium, with a liquid-applied surface of the medium facing inward. The ejection tray includes a second bending portion to bend the medium, with the liquid-applied surface of the medium facing inward. A curvature of the medium bent by the first bending portion is greater than a curvature of the medium bent by the second bending portion. The drying device dries the medium conveyed in the first bending portion.
    Type: Application
    Filed: March 13, 2019
    Publication date: September 19, 2019
    Inventors: Taku HATAKEYAMA, Takashi WATANABE, Kaoru TADOKORO, Sho OYAMATSU, Tomohiro INOUE, Hiroshi GOTOU, Mio KUMAI
  • Publication number: 20190275805
    Abstract: An ink set comprises black ink having a static surface tension A and yellow ink having a static surface tension B, wherein the static surface tension A is 28.7 mN/m or more and greater than the static surface tension B, wherein the ink set is used in an image forming device including an inkjet head including a nozzle plate including a first nozzle array and a second nozzle array disposed adjacent to the first nozzle array, the first nozzle array including multiple first nozzles configured to discharge the black ink and a second nozzle array including multiple second nozzles configured to discharge the yellow ink wherein each nozzle of the multiple first nozzles and the multiple second nozzles has a cylindrical portion having a length of 25 ?m or longer along an axial direction with an opening on an ink discharging side of the nozzle plate.
    Type: Application
    Filed: March 6, 2019
    Publication date: September 12, 2019
    Inventors: Takashi WATANABE, Taku Hatakeyama, Kaoru Tadokoro, Sho Oyamatsu, Tomohiro Inoue, Hiroshi Gotou, Mio Kumai
  • Publication number: 20190275818
    Abstract: An ink set comprises black ink having a static surface tension A and yellow ink having a static surface tension B, wherein the static surface tension A is by 0.6 mN/m or more greater than the static surface tension B, wherein the ink set is used in an image forming device including an inkjet head including a nozzle plate including a first nozzle array and a second nozzle array disposed adjacent to the first nozzle array, the first nozzle array including multiple first nozzles configured to discharge the black ink and a second nozzle array including multiple second nozzles configured to discharge the yellow ink, wherein each nozzle of the multiple first nozzles and the multiple second nozzles has a cylindrical portion having a length of 25 ?m or longer along an axial direction with an opening on an ink discharging side of the nozzle plate.
    Type: Application
    Filed: March 6, 2019
    Publication date: September 12, 2019
    Inventors: Takashi WATANABE, Taku Hatakeyama, Kaoru Tadokoro, Sho Oyamatsu, Tomohiro Inoue, Hiroshi Gotou, Mio Kumai
  • Publication number: 20190275811
    Abstract: A liquid discharge apparatus includes a conveyance path, a liquid discharge head, and a drying device. A medium is to be conveyed on the conveyance path. The liquid discharge head discharges liquid onto the medium conveyed on the conveyance path. The conveyance path includes a switchback path and an ejection path. The switchback path switches back a conveyance direction of the medium onto which the liquid has been discharged. The ejection path conveys the medium onto which the liquid has been discharged to an ejection port. The drying device dries the medium both on the switchback path and on the ejection path.
    Type: Application
    Filed: March 6, 2019
    Publication date: September 12, 2019
    Inventors: Taku HATAKEYAMA, Takashi WATANABE, Kaoru TADOKORO, Sho OYAMATSU, Tomohiro INOUE, Hiroshi GOTOU, Mio KUMAI
  • Publication number: 20190256727
    Abstract: An image forming method includes applying a pre-processing fluid to a recording medium and applying an ink to the recording medium to form an image thereon, wherein the ink comprises a magenta ink comprising water, an azo pigment, a quinacridone pigment, and an organic solvent.
    Type: Application
    Filed: February 7, 2019
    Publication date: August 22, 2019
    Inventors: Mio KUMAI, Akiyoshi SABU, Atsushi YAMAMOTO, Azumi MIYAAKE, Hidefumi NAGASHIMA, Yuri HAGA
  • Publication number: 20190100667
    Abstract: An ink includes water, a coloring material, an organic solvent having a solubility parameter of from 8.0 to 13.0, an urethane resin particle and a metal ion, wherein the organic solvent having the solubility parameter of from 8.0 to 13.0 has a proportion of from 10.0% by mass to 30.0% by mass to the ink, where the metal ion is at least one selected from an alkali metal ion and an alkaline earth metal ion, where the metal ion has a proportion of from 4000 mg/L to 8000 mg/L to the ink.
    Type: Application
    Filed: September 14, 2018
    Publication date: April 4, 2019
    Inventors: Azumi Miyaake, Kaori Miyahara, Masayuki Koyano, Mio Kumai, Ayano Momose, Satoshi Kojima, Kiminori Masuda, Amika Sagara, Hiroki Hagiwara
  • Patent number: 10030159
    Abstract: An active-energy-ray-curable composition, a cured material of the active-energy-ray-curable composition satisfying a critical load of 5.0 g or more but 25.0 g or less, the critical load being obtained by a continuous loading test method using a variable normal load friction and wear measurement device, the cured material having an average thickness of 10 ?m and being formed by coating the active-energy-ray-curable composition on a substrate and by irradiating and curing the active-energy-ray-curable composition with active energy rays having illuminance of 1.5 W/cm2 and an amount of irradiation of 200 mJ/cm2.
    Type: Grant
    Filed: March 9, 2017
    Date of Patent: July 24, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Mio Kumai, Mihoko Matsumoto, Masayuki Koyano, Kaori Miyahara, Azumi Miyaake, Yuuki Mizutani, Ayano Momose, Maiko Koeda, Yuri Haga, Hiroki Nakane, Takayuki Shimizu, Hiroki Kobayashi
  • Patent number: 9988539
    Abstract: An active-energy-ray-curable composition including active-energy-ray-polymerizable compounds, wherein the active-energy-ray-polymerizable compounds include a monofunctional monomer, a bifunctional monomer, and a trifunctional monomer, and wherein the monofunctional monomer, the bifunctional monomer, and the trifunctional monomer satisfy conditions (1) and (2) below: (1) [number of functional groups derived from the monofunctional monomer]>[number of functional groups derived from the bifunctional monomer]>[number of functional groups derived from the trifunctional monomer]; and (2) a standard deviation of functional group ratios is from 0.003 through 0.030, the functional group ratios being expressed by [number of functional groups derived from N-functional monomer]/([number of functional groups derived from the monofunctional monomer]+[number of functional groups derived from the bifunctional monomer]+[number of functional groups derived from the trifunctional monomer]), the N being mono, bi, or tri.
    Type: Grant
    Filed: October 31, 2016
    Date of Patent: June 5, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Shun Saito, Mihoko Matsumoto, Masayuki Koyano, Azumi Miyaake, Yuuki Mizutani, Mio Kumai
  • Patent number: 9874826
    Abstract: A toner, including a binder resin, a release agent, and a colorant, wherein a total amount of hydrocarbon compounds having 33 to 35 carbon atoms in the toner measured by ion attachment mass spectrometry (IAMS) is 40% to 70% in terms of a signal intensity ratio.
    Type: Grant
    Filed: October 28, 2015
    Date of Patent: January 23, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideki Sugiura, Mio Kumai
  • Patent number: 9873804
    Abstract: Active-energy-ray-curable composition including: monofunctional monomers; and polymerization initiator, cured material of the composition satisfying 0.30?D?0.85, where D is difference between peak-area-ratios A and B in infrared-ATR and obtained by: the composition is coated on polycarbonate substrate to form coated film having average thickness of 10 ?m; the film is irradiated with active energy rays having light quantity of 500 mJ/cm2 at UV intensity of 1.
    Type: Grant
    Filed: October 21, 2016
    Date of Patent: January 23, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuki Mizutani, Mihoko Matsumoto, Masayuki Koyano, Azumi Miyaake, Shun Saito, Mio Kumai
  • Publication number: 20170260405
    Abstract: An active-energy-ray-curable composition, a cured material of the active-energy-ray-curable composition satisfying a critical load of 5.0 g or more but 25.0 g or less, the critical load being obtained by a continuous loading test method using a variable normal load friction and wear measurement device, the cured material having an average thickness of 10 ?m and being formed by coating the active-energy-ray-curable composition on a substrate and by irradiating and curing the active-energy-ray-curable composition with active energy rays having illuminance of 1.5 W/cm2 and an amount of irradiation of 200 mJ/cm2.
    Type: Application
    Filed: March 9, 2017
    Publication date: September 14, 2017
    Inventors: Mio KUMAI, Mihoko Matsumoto, Masayuki Koyano, Kaori Miyahara, Azumi Miyaake, Yuuki Mizutani, Ayano Momose, Maiko Koeda, Yuri Haga, Hiroki Nakane, Takayuki Shimizu, Hiroki Kobayashi
  • Patent number: 9678450
    Abstract: Provided is [i] a toner including at least a colorant, a resin, and a releasing agent, wherein a spin-spin relaxation time (t2) of the toner at 90° C. obtained by Hahn Echo method of pulse NMR analysis is from 1.80 msec to 7.00 msec. Also provided is [ii] a toner according to [i], wherein the spin-spin relaxation time (t2) of the toner at 90° C. obtained by Hahn Echo method of pulse NMR analysis is from 3.80 msec to 5.90 msec.
    Type: Grant
    Filed: April 25, 2014
    Date of Patent: June 13, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Mio Kumai, Hideki Sugiura, Yuka Mizoguchi