Patents by Inventor Kohsuke Nagata

Kohsuke Nagata 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: 11036154
    Abstract: A toner is provided. The toner comprises a colorant, a release agent, and a binder resin. The binder resin comprises a crystalline polyester resin and an amorphous polyester resin. The amorphous polyester resin comprises an amorphous polyester resin A and an amorphous polyester resin B. The amorphous polyester resin A comprises an isocyanurate backbone and at least one of urethane bond and urea bond. The amorphous polyester resin B comprises a trimellitic acid backbone and at least one of urethane bond and urea bond.
    Type: Grant
    Filed: November 26, 2018
    Date of Patent: June 15, 2021
    Assignee: Ricoh Company, Ltd.
    Inventors: Masayuki Ukigaya, Junichi Awamura, Hiroshi Yamada, Kohsuke Nagata, Hiroyuki Takeda
  • Patent number: 10859932
    Abstract: A toner, including: a polyester resin, wherein the polyester resin has a structure represented by any one of formulas 1) to 3) below: 1) R1-(NHCONH-R2)n-, 2) R1-(NHCOO-R2)n-, and 3) R1-(OCONH-R2)n-, where n is 3 or more, R1 represents an aromatic organic group or an aliphatic organic group, and R2 represents a group derived from a resin that is polyester formed of polycarboxylic acid, polyol, or both thereof; or that is a modified polyester obtained by modifying polyester with isocyanate.
    Type: Grant
    Filed: October 8, 2015
    Date of Patent: December 8, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Sugimoto, Shinya Nakayama, Hiroshi Yamada, Hideyuki Santo, Ryuta Chiba, Suzuka Amemori, Kohsuke Nagata
  • Patent number: 10670980
    Abstract: Provided is a toner including a crystalline polyester resin including a constitutional unit derived from saturated aliphatic dicarboxylic acid and a constitutional unit derived from saturated aliphatic diol, an amorphous hybrid resin, an amorphous polyester resin, a release agent, and a colorant, wherein the crystalline polyester resin includes a constitutional unit derived from sebacic acid as the constitutional unit derived from the saturated aliphatic dicarboxylic acid, and the amorphous hybrid resin is a composite resin including a polyester-based resin unit and a styrene-based resin unit.
    Type: Grant
    Filed: July 10, 2018
    Date of Patent: June 2, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Koh Ohnuma, Tsuyoshi Sugimoto, Shinya Nakayama, Hideyuki Santo, Shin Hasegawa, Suzuka Karato, Kohsuke Nagata
  • Publication number: 20190171122
    Abstract: A toner is provided. The toner comprises a colorant, a release agent, and a binder resin. The binder resin comprises a crystalline polyester resin and an amorphous polyester resin. The amorphous polyester resin comprises an amorphous polyester resin A and an amorphous polyester resin B. The amorphous polyester resin A comprises an isocyanurate backbone and at least one of urethane bond and urea bond. The amorphous polyester resin B comprises a trimellitic acid backbone and at least one of urethane bond and urea bond.
    Type: Application
    Filed: November 26, 2018
    Publication date: June 6, 2019
    Inventors: Masayuki UKIGAYA, Junichi AWAMURA, Hiroshi YAMADA, Kohsuke NAGATA, Hiroyuki TAKEDA
  • Patent number: 10156801
    Abstract: A toner, including: a colorant; a binder resin; and a releasing agent, wherein the binder resin includes a polyester resin, and the toner satisfies requirements (1) and (2) below: (1): G?(50)?3.0×107 Pa and 1.0×105 Pa?G?(60)?1.0×107 Pa, where G?(50) is a storage modulus at 50° C. of the toner and G?(60) is a storage modulus at 60° C. of the toner; and (2): a spin-spin relaxation time of the toner at 50° C. measured by solid echo method of pulse NMR is 1.0 ms or shorter.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: December 18, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohsuke Nagata, Shinya Nakayama, Tsuyoshi Sugimoto, Daisuke Asahina, Susumu Chiba
  • Publication number: 20180321606
    Abstract: Provided is a toner including a crystalline polyester resin including a constitutional unit derived from saturated aliphatic dicarboxylic acid and a constitutional unit derived from saturated aliphatic diol, an amorphous hybrid resin, an amorphous polyester resin, a release agent, and a colorant, wherein the crystalline polyester resin includes a constitutional unit derived from sebacic acid as the constitutional unit derived from the saturated aliphatic dicarboxylic acid, and the amorphous hybrid resin is a composite resin including a polyester-based resin unit and a styrene-based resin unit.
    Type: Application
    Filed: July 10, 2018
    Publication date: November 8, 2018
    Inventors: Koh OHNUMA, Tsuyoshi Sugimoto, Shinya Nakayama, Hideyuki Santo, Shin Hasegawa, Suzuka Karato, Kohsuke Nagata
  • Patent number: 10088766
    Abstract: A layered inorganic mineral including a surface treated with a fluorine-containing compound, where the layered inoganic mineral that can be favorably used for a toner that is excellent in high charging ability, charging stability, and low temperature fixing ability, and that can exhibits high reliability during cleaning.
    Type: Grant
    Filed: November 30, 2015
    Date of Patent: October 2, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Hideyuki Santo, Tsuyoshi Sugimoto, Shinya Nakayama, Suzuka Amemori, Hiroshi Yamada, Ryuta Chiba, Kohsuke Nagata
  • Patent number: 10073366
    Abstract: A toner is provided. The toner includes an amorphous resin, a crystalline resin dispersed in the amorphous resin, and a release agent. The toner satisfies the following inequality: B/A<0.8 where A represents a perimeter of the crystalline resin and B represents a length of a part of the perimeter A of the crystalline resin at which the crystalline resin is in contact with the amorphous resin, A and B being measured from a cross-sectional image of the toner observed with transmission electron microscope.
    Type: Grant
    Filed: June 14, 2017
    Date of Patent: September 11, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohsuke Nagata, Ryuuta Yoshida, Shinya Nakayama, Tsuyoshi Sugimoto, Akinori Saitoh, Hideyuki Santo, Suzuka Karato, Koh Ohnuma, Takahiro Kadota, Shinsuke Nagai, Akihiro Takeyama
  • Patent number: 9921503
    Abstract: A toner including: a pigment; polyester resin A that is insoluble in tetrahydrofuran (THF); and polyester resin B that is soluble in THF, wherein the toner satisfies requirements (1) to (3) below: (1) the polyester resin A includes one or more aliphatic diols including from 3 through 10 carbon atoms, as a component constituting the polyester resin A; (2) the polyester resin B includes at least an alkylene glycol in an amount of 40 mol % or more, as a component constituting the polyester resin B; and (3) a glass transition temperature (Tg1st) of the toner at first heating in differential scanning calorimetry (DSC) of the toner is from 20° C. through 50° C.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: March 20, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yamada, Tsuyoshi Sugimoto, Susumu Chiba, Shinsuke Nagai, Kohsuke Nagata, Shinya Nakayama, Yuka Mizoguchi, Suzuka Amemori
  • Patent number: 9880479
    Abstract: Toner that includes a polyester resin, fluorine and aluminum. The toner satisfies formulae (1) and (2), 1.00?AB/B?0.50??(1) 0?(A?AB)/A?0.25??(2) where A represents an area where the fluorine exists measured by Energy Dispersive X-ray Spectroscopy (EDS), B represents an area where the aluminum exists measured by Energy Dispersive X-ray Spectroscopy (EDS) and AB represents an overlapping area between A and B. Toner stored unit, image forming apparatus, and image forming method.
    Type: Grant
    Filed: January 12, 2017
    Date of Patent: January 30, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hideyuki Santoh, Tsuyoshi Sugimoto, Akinori Saitoh, Shin Hasegawa, Suzuka Amemori, Kohsuke Nagata, Koh Ohnuma
  • Publication number: 20180024452
    Abstract: A toner, including: a polyester resin, wherein the polyester resin has a structure represented by any one of formulas 1) to 3) below: 1) R1-(NHCONH-R2)n-, 2) R1-(NHCOO-R2)n-, and 3) R1-(OCONH-R2)n-, where n is 3 or more, R1 represents an aromatic organic group or an aliphatic organic group, and R2 represents a group derived from a resin that is polyester formed of polycarboxylic acid, polyol, or both thereof; or that is a modified polyester obtained by modifying polyester with isocyanate.
    Type: Application
    Filed: October 8, 2015
    Publication date: January 25, 2018
    Inventors: Tsuyoshi SUGIMOTO, Shinya NAKAYAMA, Hiroshi YAMADA, Hideyuki SANTO, Ryuta CHIBA, Suzuka AMEMORI, Kohsuke NAGATA
  • Publication number: 20170371257
    Abstract: A layered inorganic mineral including a surface treated with a fluorine-containing compound, where the layered inoganic mineral that can be favorably used for a toner that is excellent in high charging ability, charging stability, and low temperature fixing ability, and that can exhibits high reliability during cleaning.
    Type: Application
    Filed: November 30, 2015
    Publication date: December 28, 2017
    Inventors: Hideyuki SANTO, Tsuyoshi SUGIMOTO, Shinya NAKAYAMA, Suzuka AMEMORI, Hiroshi YAMADA, Ryuta CHIBA, Kohsuke NAGATA
  • Publication number: 20170363980
    Abstract: A toner is provided. The toner includes an amorphous resin, a crystalline resin dispersed in the amorphous resin, and a release agent. The toner satisfies the following inequality: B/A<0.8 where A represents a perimeter of the crystalline resin and B represents a length of a part of the perimeter A of the crystalline resin at which the crystalline resin is in contact with the amorphous resin, A and B being measured from a cross-sectional image of the toner observed with transmission electron microscope.
    Type: Application
    Filed: June 14, 2017
    Publication date: December 21, 2017
    Inventors: Kohsuke NAGATA, Ryuuta YOSHIDA, Shinya NAKAYAMA, Tsuyoshi SUGIMOTO, Akinori SAITOH, Hideyuki SANTO, Suzuka KARATO, Koh OHNUMA, Takahiro KADOTA, Shinsuke NAGAI, Akihiro TAKEYAMA
  • Patent number: 9785074
    Abstract: A polyester resin for a toner, the polyester resin including: a segment derived from an alcohol component; and a segment derived from a carboxylic acid component, wherein the alcohol component includes a trivalent or higher aliphatic alcohol, and wherein the polyester resin satisfies Expressions (1) to (3) below: 500 ? Weight ? ? average ? ? molecular ? ? weight ? ? ( Mw ) ( Valence ? ? of ? ? the ? ? trivalent ? ? or higher ? ? aliphatic ? ? alcohol ) × ( Amount ? ? of ? ? the ? ? trivalent ? ? or higher ? ? aliphatic ? ? alcohol ) ? 4 , 000 ; Expression ? ? ( 1 ) 4,000?Weight average molecular weight (Mw)?25,000?? Expression (2); and 0.5?(Amount of the trivalent or higher aliphatic alcohol)?6.
    Type: Grant
    Filed: January 6, 2015
    Date of Patent: October 10, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohsuke Nagata, Shinya Nakayama, Tsuyoshi Sugimoto, Hiroshi Yamada, Susumu Chiba, Shinsuke Nagai, Suzuka Amemori
  • Patent number: 9753387
    Abstract: A toner includes a base particle including a polyester resin and a colorant. A sea-island structure is observed by a transmission electron microscope (TEM) in a cross-sectional image of the toner. The island structure includes the colorant and has an average diameter of from 0.2 ?m to 1.0 ?m, and the number of the island structure is from 5 to 30.
    Type: Grant
    Filed: May 12, 2016
    Date of Patent: September 5, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Shin Hasegawa, Tsuyoshi Sugimoto, Hideyuki Santo, Koh Ohnuma, Kohsuke Nagata, Suzuka Karato
  • Publication number: 20170199476
    Abstract: Toner that includes a polyester resin, fluorine and aluminum. The toner satisfies formulae (1) and (2), 1.00?AB/B?0.50 ??(1) 0?(A?AB)/A?0.25 ??(2) where A represents an area where the fluorine exists measured by Energy Dispersive X-ray Spectroscopy (EDS), B represents an area where the aluminum exists measured by Energy Dispersive X-ray Spectroscopy (EDS) and AB represents an overlapping area between A and B. Toner stored unit, image forming apparatus, and image forming method.
    Type: Application
    Filed: January 12, 2017
    Publication date: July 13, 2017
    Inventors: Hideyuki SANTOH, Tsuyoshi SUGIMOTO, Akinori SAITOH, Shin HASEGAWA, Suzuka AMEMORI, Kohsuke NAGATA, Koh OHNUMA
  • Patent number: 9639016
    Abstract: A toner includes a polyester resin including a polyester resin component A (A) insoluble in tetrahydrofuran; and a polyester resin component B (B) soluble in tetrahydrofuran. The toner has a first glass transition temperature (Tg1st) of from 20° C. to 50° C., measured at a first temperature rising in differential scanning calorimetry (DSC), and satisfies the following formulae (1) and (2): T=1/{a/(TgA+273)+b/(TgB+273)}?273??(1) T?TgAB>30×a??(2) wherein a and b represent weight ratios of (A) and (B) to a total weight of (A) and (B), and satisfy the equation a+b=1; and TgA, TgB and TgAB represent second glass transition temperatures (Tg2nd), measured at a second temperature rising in differential scanning calorimetry, of (A), (B), and a mixture of (A) and (B), respectively.
    Type: Grant
    Filed: February 23, 2016
    Date of Patent: May 2, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Sugimoto, Shinya Nakayama, Hiroshi Yamada, Hideyuki Santo, Shin Hasegawa, Suzuka Karato, Kohsuke Nagata, Koh Ohnuma
  • Patent number: 9557672
    Abstract: A toner, including: a polyester resin, wherein the polyester resin includes a diol component and a crosslink component as constituent components thereof, wherein the diol component contains an aliphatic diol having 3 to 10 carbon atoms in an amount of 50 mol % or more, wherein the crosslink component contains a trihydric or higher aliphatic alcohol, and wherein the toner has a glass transition temperature (Tg1st) of 20° C. to 50° C., where the glass transition temperature (Tg1st) is measured in first heating in differential scanning calorimetry (DSC) of the toner.
    Type: Grant
    Filed: August 13, 2014
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Susumu Chiba, Tsuyoshi Sugimoto, Shinya Nakayama, Kohsuke Nagata, Shinsuke Nagai, Daisuke Asahina
  • Patent number: 9557669
    Abstract: A toner, wherein the toner has glass transition temperature [Tg1st (toner)] of 20° C. to 50° C., where the glass transition temperature [Tg1st (toner)] is measured in a first heating in differential scanning calorimetry (DSC) of the toner, wherein tetrahydrofuran (THF) insoluble matter of the toner has glass transition temperature [Tg2nd (THF insoluble matter)] of ?40° C. to 30° C., where the glass transition temperature [Tg2nd (THF insoluble matter)] is measured in a second heating in differential scanning calorimetry (DSC) of the tetrahydrofuran (THF) insoluble matter, wherein the THF insoluble matter has a storage modulus at 100° C. [G?(100) (THF insoluble matter)] of 1.0×105 Pa to 1.0×107 Pa, and wherein a ratio of a storage modulus of the THF insoluble matter at 40° C. [G?(40) (THF insoluble matter)] to the storage modulus of the THF insoluble matter at 100° C. [G?(100) (THF insoluble matter)] is 3.5×10 or less.
    Type: Grant
    Filed: August 29, 2014
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinsuke Nagai, Shinya Nakayama, Tsuyoshi Sugimoto, Susumu Chiba, Kohsuke Nagata, Daisuke Asahina
  • Patent number: 9557671
    Abstract: A toner, including: base particles containing a polyester resin, a colorant, and a release agent, wherein the toner has a glass transition temperature (Tg1st) of 20° C. to 50° C. where the glass transition temperature (Tg1st) is measured in first heating of differential scanning calorimetry (DSC) of the toner, wherein tetrahydrofuran (THF) insoluble matter of the toner has a glass transition temperature [Tg2nd (THF insoluble matter)] of 30° C. or lower where the glass transition temperature [Tg2nd (THF insoluble to matter)] is measured in second heating of differential scanning calorimetry (DSC) of the THF insoluble matter, and wherein 50% or less of the colorant is present within a region of 1,000 nm from a surface of each of the base particles toward a center thereof.
    Type: Grant
    Filed: February 24, 2015
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryuta Chiba, Shinya Nakayama, Hiroshi Yamada, Minoru Masuda, Akinori Saitoh, Hideyuki Santo, Shinsuke Nagai, Akihiro Takeyama, Hiroyuki Takeda, Tsuyoshi Sugimoto, Suzuka Amemori, Kohsuke Nagata