Patents by Inventor Koichiro OYAMA

Koichiro OYAMA 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: 11760893
    Abstract: An ink including a pigment, water, and a resin is provided. An image formed with the ink on a print medium has a tack force of 6 gf or greater but 13 gf or less when measured at a probe temperature of 100 degrees C., where the image is a solid image formed at a resolution of 1,200 dpi, subsequently irradiated with light of 395 nm for 0.6 seconds, and left to stand at normal temperatures and normal humidities for 30 seconds.
    Type: Grant
    Filed: July 8, 2021
    Date of Patent: September 19, 2023
    Assignee: Ricoh Company, Ltd.
    Inventors: Kento Sugita, Yuuki Yokohama, Azumi Miyaake, Satoshi Takahashi, Koichiro Oyama, Mizuki Kuroha
  • Publication number: 20220251409
    Abstract: A liquid composition contains a macrocyclic compound enclosing a metal ion, water, and an organic solvent, wherein a recording medium where the liquid composition has been applied has at least one of an antibacterial activity or an antiviral activity.
    Type: Application
    Filed: January 27, 2022
    Publication date: August 11, 2022
    Applicant: Ricoh Company, Ltd.
    Inventors: Shun SAITO, Kento Sugita, Koichiro Oyama, Mizuki Kuroha, Satoshi Takahashi, Yuuki Yokohama, Takashi Watanabe
  • Publication number: 20220010155
    Abstract: An ink including a pigment, water, and a resin is provided. An image formed with the ink on a print medium has a tack force of 6 gf or greater but 13 gf or less when measured at a probe temperature of 100 degrees C., where the image is a solid image formed at a resolution of 1,200 dpi, subsequently irradiated with light of 395 nm for 0.6 seconds, and left to stand at normal temperatures and normal humidities for 30 seconds.
    Type: Application
    Filed: July 8, 2021
    Publication date: January 13, 2022
    Inventors: Kento SUGITA, Yuuki YOKOHAMA, Azumi MIYAAKE, Satoshi TAKAHASHI, Koichiro OYAMA, Mizuki KUROHA
  • Publication number: 20210292582
    Abstract: Provided is an ink including: a pigment-containing matter containing a pigment; an organic solvent; water; and a compound represented by General Formula (1) below. A difference (Ra?R0) is 2.0 or less, where Ra is a distance between a Hansen solubility parameter of the organic solvent and a Hansen solubility parameter of the pigment-containing matter determined by a Hansen solubility sphere method, and R0 is an interaction radius of the pigment-containing matter determined by the Hansen solubility sphere method. In the General Formula (1), R1, R2, R3, and R4 each independently represent a hydrogen atom or an alkyl group having 1 or more but 5 or less carbon atoms, and n represents an integer of 3 or more but 11 or less.
    Type: Application
    Filed: March 10, 2021
    Publication date: September 23, 2021
    Inventors: Atsufumi HANAZAWA, Yuuki YOKOHAMA, Takashi TAMAI, Yukihiro IMANAGA, Kento SUGITA, Azumi MIYAAKE, Sayuri KOJIMA, Toru YOSHIKAWA, Koichiro OYAMA, Satoshi TAKAHASHI, Mizuki KUROHA
  • Publication number: 20210238432
    Abstract: An ink contains water, an organic solvent, a resin, and a pigment, wherein the organic solvent has a Hansen solubility parameter (HSP) value in a Hansen sphere in a ?D axis, ?P axis, and ?H axis coordinate space of a solid content of the ink.
    Type: Application
    Filed: February 2, 2021
    Publication date: August 5, 2021
    Inventors: Toru YOSHIKAWA, Yuuki YOKOHAMA, Takashi TAMAI, Satoshi TAKAHASHI, Sayuri KOJIMA, Atsufumi HANAZAWA, Azumi MIYAAKE, Yukihiro IMANAGA, Koichiro OYAMA, Kento SUGITA, Mizuki KUROHA
  • Patent number: 10844235
    Abstract: Ink includes water, a coloring material, and a copolymer including a first structure unit represented by the following Chemical formula 1 and a second structure unit including an anionic group. In the Chemical formula, R represents a hydrogen atom or a methyl group, X represents an alkylene group having 2-4 carbon atoms, and Y represents a substituted or non-substituted straight-chain alkylene group having 5 to 7 carbon atoms.
    Type: Grant
    Filed: January 8, 2019
    Date of Patent: November 24, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuusuke Koizuka, Kazukiyo Nagai, Tomoyuki Shimada, Shigeyuki Harada, Akihiko Matsuyama, Yoshiki Yanagawa, Koichiro Oyama, Takuya Yamazaki, Akiyoshi Sabu
  • Patent number: 10836171
    Abstract: An ink and cleaning liquid set includes an ink comprising a coloring material and a resin and a cleaning liquid comprising water and at least one type of organic solvent, wherein the ink in a dried form has a glass transition temperature of from 40 to 90 degrees C. and the swelling ratio calculated from a mass of a film of the ink in a dried form before and after immersion in the cleaning liquid is 10 percent or greater according to the following relationship 1: swelling ratio (percent)=100×[(B?A)/A] Relationship 1, where A represents the mass of the film before the immersion and B represents the mass of the film after the immersion.
    Type: Grant
    Filed: July 10, 2019
    Date of Patent: November 17, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Amika Sagara, Yuuki Yokohama, Masaki Kudo, Yuusuke Koizuka, Akihiko Matsuyama, Koichiro Oyama
  • Patent number: 10807377
    Abstract: An ink, includes water; a coloring material; and a cross-linked copolymer having a structure unit represented by the following Chemical formula 1, and a structure unit represented by the following Chemical formula 2, in Chemical formula 1, X represents a hydrogen atom or a cation and R1 represents a hydrogen atom or a methyl group, in Chemical formula 2, R2 represents a hydrogen atom or a methyl group, L represents an alkylene group having 2 to 18 carbon atoms, and * represents an atomic bond.
    Type: Grant
    Filed: March 5, 2019
    Date of Patent: October 20, 2020
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuya Yamazaki, Shigeyuki Harada, Takuya Saiga, Hiroshi Gotou, Yuusuke Koizuka, Koichiro Oyama
  • Publication number: 20200016898
    Abstract: An ink and cleaning liquid set includes an ink comprising a coloring material and a resin and a cleaning liquid comprising water and at least one type of organic solvent, wherein the ink in a dried form has a glass transition temperature of from 40 to 90 degrees C. and the swelling ratio calculated from a mass of a film of the ink in a dried form before and after immersion in the cleaning liquid is 10 percent or greater according to the following relationship 1: swelling ratio (percent)=100×[(B?A)/A] Relationship 1, where A represents the mass of the film before the immersion and B represents the mass of the film after the immersion.
    Type: Application
    Filed: July 10, 2019
    Publication date: January 16, 2020
    Inventors: Amika SAGARA, Yuuki YOKOHAMA, Masaki KUDO, Yuusuke KOIZUKA, Akihiko MATSUYAMA, Koichiro OYAMA
  • Publication number: 20190276694
    Abstract: An ink comprises water, a coloring material, and a cross-linked material comprising a structure unit represented by the following Chemical formula 1 and a structure unit represented by the following Chemical formula 2, in Chemical formula 1, X represents a hydrogen atom or a cation and R1 represents a hydrogen atom or a methyl group, in Chemical formula 2, R2 represents a hydrogen atom or a methyl group, L represents an alkylene group having 2 to 18 carbon atoms, and * represents an atomic bond.
    Type: Application
    Filed: March 5, 2019
    Publication date: September 12, 2019
    Inventors: Takuya YAMAZAKI, Shigeyuki HARADA, Takuya SAIGA, Hiroshi GOTOU, Yuusuke KOIZUKA, Koichiro OYAMA
  • Patent number: 10323134
    Abstract: A particulate polyamide is provided. The particulate polyamide is porous and includes at least one of polyamide 4 and polyamide 3. In addition, the particulate polyamide has a particle diameter (d50) of from 10 ?m to 1,000 ?m and a particle diameter dispersion degree (Dv/Dn) of not greater than 3.0, wherein Dv represents the volume average particle diameter of the particulate polyamide, and Dn represents the number average particle diameter of the particulate polyamide.
    Type: Grant
    Filed: September 17, 2018
    Date of Patent: June 18, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoko Arai, Atsumi Yamabe, Koichiro Oyama, Yasuo Kamada
  • Publication number: 20190136076
    Abstract: Ink includes water, a coloring material, and a copolymer including a first structure unit represented by the following Chemical formula 1 and a second structure unit including an anionic group. In the Chemical formula, R represents a hydrogen atom or a methyl group, X represents an alkylene group having 2-4 carbon atoms, and Y represents a substituted or non-substituted straight-chain alkylene group having 5 to 7 carbon atoms.
    Type: Application
    Filed: January 8, 2019
    Publication date: May 9, 2019
    Inventors: Yuusuke Koizuka, Kazukiyo Nagai, Tomoyuki Shimada, Shigeyuki Harada, Akihiko Matsuyama, Yoshiki Yanagawa, Koichiro Oyama, Takuya Yamazaki, Akiyoshi Sabu
  • Patent number: 10273373
    Abstract: Provided is an ink containing water, a coloring material, and a copolymer, wherein the copolymer contains a structural unit represented by any one of general formulae (1a), (1b), and (1c) below and a structural unit containing an anionic group, where R1 represents a hydrogen atom or a methyl group, a represents an integer of from 6 through 10, and b represents an integer of 0 or 1, where R2 represents a hydrogen atom or a methyl group, c represents an integer of 3 or 4, and d represents an integer of 0 or 1, where R3 represents a hydrogen atom or a methyl group and e represents an integer of from 2 through 10.
    Type: Grant
    Filed: March 9, 2017
    Date of Patent: April 30, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuusuke Koizuka, Kazukiyo Nagai, Tomoyuki Shimada, Shigeyuki Harada, Koichiro Oyama, Takuya Yamazaki, Akiyoshi Sabu, Yoshiki Yanagawa, Akihiko Matsuyama
  • Patent number: 10233341
    Abstract: Ink includes water, a coloring material, and a copolymer including a first structure unit represented by the following Chemical formula 1 and a second structure unit including an anionic group. In the Chemical formula, R represents a hydrogen atom or a methyl group, X represents an alkylene group having 2-4 carbon atoms, and Y represents a substituted or non-substituted straight-chain alkylene group having 5 to 7 carbon atoms.
    Type: Grant
    Filed: September 30, 2016
    Date of Patent: March 19, 2019
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuusuke Koizuka, Kazukiyo Nagai, Tomoyuki Shimada, Shigeyuki Harada, Akihiko Matsuyama, Yoshiki Yanagawa, Koichiro Oyama, Takuya Yamazaki, Akiyoshi Sabu
  • Publication number: 20190016867
    Abstract: A particulate polyamide is provided. The particulate polyamide is porous and includes at least one of polyamide 4 and polyamide 3. In addition, the particulate polyamide has a particle diameter (d50) of from 10 ?m to 1,000 ?m and a particle diameter dispersion degree (Dv/Dn) of not greater than 3.0, wherein Dv represents the volume average particle diameter of the particulate polyamide, and Dn represents the number average particle diameter of the particulate polyamide.
    Type: Application
    Filed: September 17, 2018
    Publication date: January 17, 2019
    Applicant: RICOH COMPANY, LTD.
    Inventors: Yoko ARAI, Atsumi YAMABE, Koichiro OYAMA, Yasuo KAMADA
  • Patent number: 10138344
    Abstract: A particulate polyamide is provided. The particulate polyamide is porous and includes at least one of polyamide 4 and polyamide 3. In addition, the particulate polyamide has a particle diameter (d50) of from 10 ?m to 1,000 ?m and a particle diameter dispersion degree (Dv/Dn) of not greater than 3.0, wherein Dv represents the volume average particle diameter of the particulate polyamide, and Dn represents the number average particle diameter of the particulate polyamide.
    Type: Grant
    Filed: March 18, 2016
    Date of Patent: November 27, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Yoko Arai, Atsumi Yamabe, Koichiro Oyama, Yasuo Kamada
  • Patent number: 10000656
    Abstract: An ink includes a pigment a quinacridone compound represented by Chemical formula 1, and a copolymer including the structure unit represented by Chemical formula 2 or Chemical formula 3. In Chemical formula 1, R1, R2, R3, and R4 each, independently represent hydrogen atoms, halogen atoms, or alkyl groups having 1-4 carbon atoms, R5, R6, and R7 each, independently represent alkyl groups having 1-4 carbon atoms or alkylene groups having 1-4 carbon atoms, and m represents 1 or 2, In Chemical formula 2, R8 represents a hydrogen atom or a methyl group and L1 represents an alkylene group having 2-16 carbon atoms, In Chemical formula 3, R9 represents a hydrogen atom or a methyl group, L2 represents a single bond or —(CH2)n—O— and n represents an integer of 2-16.
    Type: Grant
    Filed: December 9, 2016
    Date of Patent: June 19, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiki Yanagawa, Akihiko Matsuyama, Kazukiyo Nagai, Tomoyuki Shimada, Shigeyuki Harada, Akiyoshi Sabu, Yuusuke Koizuka, Koichiro Oyama, Takuya Yamazaki
  • Patent number: 9896530
    Abstract: A copolymer including a structural unit represented by General Formula (1) below and a structural unit represented by General Formula (2) below, where, in General Formula (1), R is a hydrogen atom or a methyl group and X is a hydrogen atom or a cation, where, in General Formula (2), L is an alkylene group having 2 or more but 18 or less carbon atoms.
    Type: Grant
    Filed: December 1, 2016
    Date of Patent: February 20, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigeyuki Harada, Kazukiyo Nagai, Yuusuke Koizuka, Tomoyuki Shimada, Takuya Yamazaki, Koichiro Oyama, Akiyoshi Sabu, Akihiko Matsuyama, Yoshiki Yanagawa
  • Publication number: 20170267884
    Abstract: Provided is an ink containing water, a coloring material, and a copolymer, wherein the copolymer contains a structural unit represented by any one of general formulae (1a), (1b), and (1c) below and a structural unit containing an anionic group, where R1 represents a hydrogen atom or a methyl group, a represents an integer of from 6 through 10, and b represents an integer of 0 or 1, where R2 represents a hydrogen atom or a methyl group, c represents an integer of 3 or 4, and d represents an integer of 0 or 1, where R3 represents a hydrogen atom or a methyl group and e represents an integer of from 2 through 10.
    Type: Application
    Filed: March 9, 2017
    Publication date: September 21, 2017
    Inventors: Yuusuke KOIZUKA, Kazukiyo NAGAI, Tomoyuki SHIMADA, Shigeyuki HARADA, Koichiro OYAMA, Takuya YAMAZAKI, Akiyoshi SABU, Yoshiki YANAGAWA, Akihiko MATSUYAMA
  • Publication number: 20170174918
    Abstract: An ink includes a pigment a quinacridone compound represented by Chemical formula 1, and a copolymer including the structure unit represented by Chemical formula 2 or Chemical formula 3. In Chemical formula 1, R1, R2, R3, and R4 each, independently represent hydrogen atoms, halogen atoms, or alkyl groups having 1-4 carbon atoms, R5, R6, and R7 each, independently represent alkyl groups having 1-4 carbon atoms or alkylene groups having 1-4 carbon atoms, and m represents 1 or 2, In Chemical formula 2, R8 represents a hydrogen atom or a methyl group and L1 represents an alkylene group having 2-16 carbon atoms, In Chemical formula 3, R9 represents a hydrogen atom or a methyl group, L2 represents a single bond or —(CH2)n—O— and n represents an integer of 2-16.
    Type: Application
    Filed: December 9, 2016
    Publication date: June 22, 2017
    Inventors: Yoshiki YANAGAWA, Akihiko MATSUYAMA, Kazukiyo NAGAI, Tomoyuki SHIMADA, Shigeyuki HARADA, Akiyoshi SABU, Yuusuke KOIZUKA, Koichiro OYAMA, Takuya YAMAZAKI