Patents by Inventor Kazukiyo Nagai

Kazukiyo 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: 20150064425
    Abstract: An ink composition contains a pigment; a copolymer comprising a phosphoric acid group or phosphonic acid group; a hydrosoluble solvent; and water, wherein the pigment is represented by the following chemical formula 1 and satisfies the following relation 1: Y/X?0.20??Relation 1 where X represents a peak intensity at a Bragg (2?±0.2°) angle in a range of 2? of from 26.5° to 27.5° and Y represents a peak intensity at a Bragg (2?±0.2°) angle in a range of 2? of from 11.0° to 11.5° to a CuK? X-ray having a wavelength of 1.541 ?.
    Type: Application
    Filed: August 11, 2014
    Publication date: March 5, 2015
    Inventors: Akihiko MATSUYAMA, Mitsuru Naruse, Masayasu Nonogaki, Kazukiyo Nagai, Keita Katoh, Yuusuke Koizuka
  • Publication number: 20150056425
    Abstract: An ink for inkjet recording includes water; a hydrosoluble solvent, a pigment, and a copolymer including a salt of a diphosphonic acid group. The copolymer including a salt of a diphosphonic acid group includes structural units having the following formulae (1) and (2): X represents an alkylene group having 1 to 3 carbon atoms, each of R1 and R2 represents a hydrogen atom or a methyl group, M+ represents an alkali metal ion, an organic ammonium ion or a proton and Z1 represents a hydrocarbon group having 6 to 22 carbon atoms. The alkali metal ion or the organic ammonium ion and the proton may be mixed, and half or more of the M+ are alkali metal ions or the organic ammonium ions.
    Type: Application
    Filed: August 6, 2014
    Publication date: February 26, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Kazukiyo Nagai, Yuusuke KOIZUKA, Mitsuru NARUSE, Masayasu NONOGAKI, Akihiko MATSUYAMA, Keita KATOH, Shigeyuki HARADA, Masayuki FUKUOKA
  • Patent number: 8960885
    Abstract: An ink for inkjet recording, which is used for recording on a paper having a concentration of an eluted Ca ion of from 1.0×10?4 to 5.0×10?4 g/g when dipped in pure water. The ink includes at least a pigment, a pigment dispersant, a water-soluble organic solvent and water. The pigment dispersant is a copolymer synthesized using at least (1) unsaturated ethylene monomer having a phosphoric acid group or a phosphonic acid group and (2) unsaturated ethylene monomer having an alkyl group having 12 to 22 carbon atoms.
    Type: Grant
    Filed: December 4, 2013
    Date of Patent: February 24, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Keita Katoh, Mitsuru Naruse, Akihiko Matsuyama, Masayasu Nonogaki, Minoru Hakiri, Kazukiyo Nagai, Yuusuke Koizuka
  • Patent number: 8871412
    Abstract: To provide an electrophotographic photoconductor, which contains a layer containing a cured product obtained by crosslinking (i) a compound containing a charge-transporting group and three or more methylol groups, and (ii) a compound containing a charge-transporting group, which is other than the compound containing a charge-transporting group and three or more methylol groups.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: October 28, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuji Tanaka, Norio Nagayama, Kazukiyo Nagai
  • Publication number: 20140267516
    Abstract: An inkjet recording ink, including: water; a water-soluble solvent; a pigment; and a phosphate group-containing copolymer, wherein the phosphate group-containing copolymer includes a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2): wherein, in the general formula (1), R1 represents either of a hydrogen atom and a methyl group; and M+ represents any of an alkali metal ion, an organic amine ion and a hydrogen ion, one-half or more of the M+ in the copolymer is an alkali metal ion or an organic amine, and the remainder is a hydrogen ion; wherein, in the general formula (2), R2 represents either of a hydrogen atom and a methyl group.
    Type: Application
    Filed: March 10, 2014
    Publication date: September 18, 2014
    Applicant: Ricoh Company, Ltd.
    Inventors: Masayasu Nonogaki, Keita Katoh, Minoru Hakiri, Mitsuru Naruse, Akihiko Matsuyama, Kazukiyo Nagai, Yuusuke Koizuka, Nobuyuki Sakamoto, Yosuke Matsuoka, Masatomo Takahashi
  • Publication number: 20140275401
    Abstract: An inkjet recording ink, including: water; a water-soluble solvent; a pigment; and a phosphate group-containing copolymer, wherein the phosphate group-containing copolymer includes a structural unit represented by the following general formula (1) and a structural unit represented by the following structural formula (1): wherein, in the general formula (1), R1 represents either of a hydrogen atom and a methyl group; and M+ represents any of an alkali metal ion, an organic ammonium ion, an organic amine ion and a hydrogen ion, one-half or more of the M+ in the copolymer is an alkali metal ion, an organic ammonium ion or an organic amine, and the remainder is a hydrogen ion:
    Type: Application
    Filed: March 10, 2014
    Publication date: September 18, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Keita Katoh, Mitsuru NARUSE, Akihiko MATSUYAMA, Masayasu Nonogaki, Minoru Hakiri, Yuusuke Koizuka, Kazukiyo Nagai, Nobuyuki Sakamoto, Yosuke Matsuoka, Masatomo Takahashi
  • Patent number: 8835084
    Abstract: An electrophotographic photoreceptor including an electroconductive substrate, a charge generation layer located overlying the electroconductive substrate, a hole transport layer located on the charge generation layer, and a hole transport protective layer located on the hole transport layer. The hole transport protective layer includes a three-dimensionally crosslinked material obtained by irradiating a composition including at least a radically polymerizable hole transport compound with ultraviolet rays or electron beams so that the radically polymerizable hole transport compound causes chain polymerization. In addition, the protective layer includes a specific cyano-containing styryl aromatic compound or a specific cyano-containing distyryl aromatic compound.
    Type: Grant
    Filed: September 22, 2011
    Date of Patent: September 16, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazukiyo Nagai, Tetsuro Suzuki, Hongguo Li
  • Publication number: 20140242352
    Abstract: An inkjet ink that contains at least water; a water-soluble organic solvent; a pigment; and a copolymer or a salt thereof. The copolymer or the salt thereof has at least a structural unit represented by Formula 1, a structural unit represented by Formula 2, and a structural unit represented by Formula 3 or 4. In Formula 1, R1 represents a methyl group or a hydrogen atom, M+s each represent a hydrogen ion, an alkali metal ion, or an organic ammonium ion, and m and n each, independently represent 0 or an integer of from 1 to 6 excluding a case of both m and n being 0 at the same time. In Formula 2, R2 represents a methyl group or a hydrogen atom. In Formula 3, R3 represents a methyl group or a hydrogen atom.
    Type: Application
    Filed: February 19, 2014
    Publication date: August 28, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Mitsuru Naruse, Masayasu Nonogaki, Keita Katoh, Akihiko Matsuyama, Kazukiyo Nagai, Yuusuke Koizuka
  • Publication number: 20140199530
    Abstract: An ink for inkjet recording, which is used for recording on a paper having a concentration of an eluted Ca ion of from 1.0×10?4 to 5.0×10?4 g/g when dipped in pure water. The ink includes at least a pigment, a pigment dispersant, a water-soluble organic solvent and water. The pigment dispersant is a copolymer synthesized using at least (1) unsaturated ethylene monomer having a phosphoric acid group or a phosphonic acid group and (2) unsaturated ethylene monomer having an alkyl group having 12 to 22 carbon atoms.
    Type: Application
    Filed: December 4, 2013
    Publication date: July 17, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Keita KATOH, Mitsuru NARUSE, Akihiko MATSUYAMA, Masayasu NONOGAKI, Minoru HAKIRI, Kazukiyo NAGAI, Yuusuke KOIZUKA
  • Patent number: 8771909
    Abstract: An electrophotographic photoconductor including: an electrically conductive substrate; and at least a photoconductive layer on the electrically conductive substrate, wherein the electrophotographic photoconductor includes an uppermost surface layer, and the uppermost surface layer includes an inorganic filler, an acidic disperser and a three-dimensionally crosslinked polymer, wherein the three-dimensionally crosslinked polymer is formed through polymerization among compounds each containing a charge transporting compound and three or more [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups where the charge transporting compound has one or more aromatic rings and the [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups are bound to the aromatic rings of the charge transporting compound, and wherein the polymerization proceeds after some of the [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups have been partially cleaved and eliminated with an acid catalyst.
    Type: Grant
    Filed: November 6, 2012
    Date of Patent: July 8, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuusuke Koizuka, Yuuji Tanaka, Kazukiyo Nagai, Tetsuro Suzuki
  • Publication number: 20140178810
    Abstract: An image bearing member includes a substrate, and a photosensitive layer overlying the substrate, wherein an uppermost surface layer of the image bearing member has a hydrocarbon compound represented by the following Chemical Formula 1; and a three-dimensionally cross-linked polymer formed by polymerization reaction of a charge transport compound having three or more [tetrahydro-2H-pyran-2-yl)oxy]methyl groups linked with aromatic rings, wherein, in the polymerization reaction, part of the three or more [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups is severed and detached from the charge transport compound, Ph1-Q1-Ph2-Q2-Ph3??Chemical Formula 1 where Q1 and Q2 independently represent methylene groups or ethylene groups, Ph1 and Ph3 independently represent phenyl groups with which one or two methyl groups are bonded, and Ph2 represents a phenylene group or a phenylene group having one methyl group.
    Type: Application
    Filed: December 4, 2013
    Publication date: June 26, 2014
    Inventors: Kazukiyo NAGAI, Yuuji Tanaka, Tetsuro Suzuki, Yuusuke Koizuka
  • Publication number: 20140141209
    Abstract: An ink for inkjet recording includes water; a water-soluble solvent; a pigment; and a copolymer including a salt of phosphonic acid group.
    Type: Application
    Filed: October 10, 2013
    Publication date: May 22, 2014
    Inventors: Yuusuke KOIZUKA, Kazukiyo Nagai, Mitsuru Naruse, Masayasu Nonogaki, Minoru Hakiri, Akihiko Matsuyama, Keita Katoh
  • Publication number: 20140120331
    Abstract: An ink for inkjet recording includes water, a water-soluble solvent, a pigment and a copolymer including a salt of phosphonic acid group. The copolymer including a salt of phosphonic acid group includes structural units having the following formulae (1) and (2) or (3): wherein not less than half or all of M+ represent a cation of alkali metals or an organic ammonium ion, and the rest represents proton; wherein Ar1 represents a monovalent group of benzene or naphthalene; and wherein R1 represents an alkyl group having 5 to 20 carbon atoms.
    Type: Application
    Filed: October 2, 2013
    Publication date: May 1, 2014
    Inventors: Yuusuke KOIZUKA, Kazukiyo Nagai, Mitsuru Naruse, Masayasu Nonogaki, Minoru Hakiri, Akihiko Matsuyama, Keita Katoh
  • Publication number: 20140092180
    Abstract: An ink composition contains a pigment represented by the following chemical formula 1; a hydrosoluble solvent; and water, wherein the pigment satisfies the following relation 1: 0.040<Y/X<0.200 (Relation 1), where, in a CuK? X-ray diffraction spectrum having a wavelength of 1.541 ?, X represents a peak intensity at a Bragg (2?±0.2°) angle in a range of 2? of from 26.5° to 27.5° and Y represents a peak intensity at a Bragg (2?±0.2°) angle in a range of 2? of from 11.0° to 11.
    Type: Application
    Filed: September 12, 2013
    Publication date: April 3, 2014
    Inventors: Akihiko Matsuyama, Mitsuru Naruse, Masayasu Nonogaki, Minoru Hakiri, Keita Katoh, Kazukiyo Nagai, Yuusuke Koizuka
  • Patent number: 8679712
    Abstract: A photoreceptor including an electroconductive substrate; and a photosensitive layer overlying the electroconductive substrate, wherein the uppermost surface layer of the photosensitive layer has a three-dimensional cross-linked product formed by polymerization reaction of a charge transport compound A represented by the following Chemical Structure 1 and a charge transport compound B having three or more [tetrahydro-2H-pyran-2-yl)oxy]methyl groups linked with aromatic rings in which part of the [tetrahydro-2H-pyran-2-yl)oxy]methyl groups is severed and detached. In the Chemical Structure 1, Ar1 represents an aromatic hydrocarbon group having 6 to 20 carbon atoms that may have an alkyl group having one to four carbon atoms as a substitution group.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: March 25, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuji Tanaka, Kazukiyo Nagai, Tetsuro Suzuki, Yuusuke Koizuka
  • Patent number: 8669030
    Abstract: A photoreceptor including an electroconductive substrate; a photosensitive layer which is located overlying the electroconductive substrate and which is not radically crosslinked; and an outermost layer which is located overlying the photosensitive layer and which includes a radically crosslinked material, wherein the radically crosslinked material includes a unit having a specific formula. An image forming method, an image forming apparatus, and a process cartridge, which use the photoreceptor.
    Type: Grant
    Filed: December 11, 2007
    Date of Patent: March 11, 2014
    Assignee: Ricoh Company, Limited
    Inventors: Yukio Fujiwara, Tetsuro Suzuki, Kazukiyo Nagai, Hiroshi Tamura, Hiroshi Ikuno, Hidetoshi Kami
  • Patent number: 8652713
    Abstract: A furan derivative represented by the following General Formula (1): where Ar1 and Ar2 each independently represent an aryl group which may have a substituent, and R1 represents a C1-C6 alkylene group.
    Type: Grant
    Filed: September 6, 2010
    Date of Patent: February 18, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Hongguo Li, Kazukiyo Nagai, Tetsuro Suzuki, Yuuji Tanaka
  • Patent number: 8623577
    Abstract: To provide: a latent electrostatic image bearing member including one of a cured material obtained through radical polymerization of a radically polymerizable compound of component (A1), and a cured material obtained through radical polymerization of a radically polymerizable compound of component (A2) in the outermost layer, wherein the component (A1) includes two radically polymerizable groups and a substituted amino group which does not include a radically polymerizable group in a molecule, and the radically polymerizable group and the nearest substituted amino group which does not include an unsaturated bond in between are connected with two or more aromatic hydrocarbon compounds, and, the radically polymerizable compound of component (A2) includes a condensed polycyclic aromatic hydrocarbon formed by bonding a radically polymerizable group and a non-radically polymerizable substituted amine group through a condensed polycyclic aromatic hydrocarbon group; and an image forming apparatus, image forming meth
    Type: Grant
    Filed: November 9, 2007
    Date of Patent: January 7, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Tamotsu Horiuchi, Kazukiyo Nagai, Hongguo Li, Tetsuro Suzuki, Hiroshi Tamura
  • Publication number: 20130295497
    Abstract: An electrophotographic photoconductor including: a conductive substrate; and at least a photoconductive layer on the conductive substrate, wherein an uppermost surface layer of the photoconductive layer includes a three-dimensionally crosslinked film formed through polymerization among compounds each containing a charge transporting compound and three or more [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups where the charge transporting compound has one or more aromatic rings and the [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups are bound to the aromatic rings of the charge transporting compound, wherein the polymerization starts after some of the [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups have been partially cleaved and eliminated, and wherein the three-dimensionally crosslinked film has a dielectric constant of lower than 3.5.
    Type: Application
    Filed: January 12, 2012
    Publication date: November 7, 2013
    Inventors: Yuuji Tanaka, Kazukiyo Nagai, Tetsuro Suzuki, Yuusuke Koizuka
  • Publication number: 20130295496
    Abstract: An electrophotographic photoconductor including: a conductive substrate; and at least a photoconductive layer on the conductive substrate, wherein an uppermost surface layer of the photoconductive layer includes a three-dimensionally crosslinked film formed through polymerization among compounds each containing a charge transporting compound and three or more [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups where the charge transporting compound has one or more aromatic rings and the [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups are bound to the aromatic rings of the charge transporting compound, wherein the polymerization starts after some of the [(tetrahydro-2H-pyran-2-yl)oxy]methyl groups have been partially cleaved and eliminated, and wherein the three-dimensionally cross-linked film has an ionization potential of 5.4 or higher.
    Type: Application
    Filed: January 12, 2012
    Publication date: November 7, 2013
    Inventors: Yuuji Tanaka, Kazukiyo Nagai, Tetsuro Suzuki, Yuusuke Koizuka