Patents by Inventor Yukiko Nakajima

Yukiko Nakajima 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: 20130244153
    Abstract: A development agent containing toner that contains a binder resin having a crystalline resin that has a urethane and/or urea bond in its main chain, a coloring agent, and an organically modified inorganic laminate compound in which organic ions are at least partially substituted for ions present between layers of the organically modified inorganic laminate compound, and toner carrier that contains a core material whose surface is coated with a coating layer having a condensed compound of a melamine resin and/or a guanamine resin and an acrylic resin having a hydroxyl group.
    Type: Application
    Filed: March 4, 2013
    Publication date: September 19, 2013
    Inventors: Shinya NAKAYAMA, Atsushi Yamamoto, Yukiko Nakajima, Masahide Yamada, Hideyuki Santo, Suzuka Amemori
  • Publication number: 20130244011
    Abstract: A colorless transparent toner containing a crystalline resin having a urethane bond and/or a urea bond.
    Type: Application
    Filed: February 4, 2013
    Publication date: September 19, 2013
    Inventors: Akiyoshi SABU, Shinya NAKAYAMA, Atsushi YAMAMOTO, Yukiko NAKAJIMA, Hideyuki SANTO
  • Publication number: 20130236826
    Abstract: A toner for electrophotography, which is prepared by a method including dissolving or dispersing a toner composition including at least a binder resin, or binder resin and a binder resin precursor as a resin component; and a colorant in an organic solvent to form an oil phase; emulsifying or dispersing the oil phase in an aqueous medium to form an emulsion dispersion comprising emulsified particles; converging the emulsified particles to granulate mother toner particles, including controlling a temperature of the emulsion dispersion to control a circularity of the mother toner particles; and removing the organic solvent, wherein the resin component includes a crystalline resin in an amount not less than 50% by weight, and the mother toner particles have an average circularity of from 0.940 to 0.980.
    Type: Application
    Filed: December 10, 2012
    Publication date: September 12, 2013
    Inventors: Keiji MAKABE, Masahide Yamada, Shinya Nakayama, Atsushi Yamamoto, Hideyuki Santo, Yukiko Nakajima, Daiki Yamashita, Kazumi Suzuki, Tatsuya Morita, Shingo Sakashita
  • Publication number: 20130202996
    Abstract: The toner includes a pigment; and a block copolymer having a polyester block A including a residual group of a hydroxycarboxylic acid, and a polyester block B including an anionic group. When cross-section of the block copolymer is observed by a tapping mode atomic force microscope to obtain a phase image of the cross-section, the polyester block B, which has relatively large phase delay, is dispersed as domains having an average size of from 20 nm to 100 nm in a domain of the polyester block A, which has relatively small phase delay. The block copolymer has a first glass transition temperature of from ?20° C. to 20° C., and a second glass transition temperature of from 35° C. to 65° C. when the first and second glass transition temperatures are determined from a thermogram obtained by subjecting the block copolymer to differential scanning calorimetry (DSC) at a temperature rising speed of 5° C./min.
    Type: Application
    Filed: December 17, 2012
    Publication date: August 8, 2013
    Inventors: Yoshitaka Yamauchi, Masahide Yamada, Yoshihiro Moriya, Taichi Nemoto, Yukiko Nakajima, Keiji Makabe, Daiki Yamashita, Suzuka Amemori, Akiyoshi Sabu
  • Publication number: 20130171550
    Abstract: To provide a toner including at least a binder resin and a colorant, wherein the binder resin has two glass transition temperatures Tg1 and Tg2 in a differential scanning calorimetry at a heating speed of 5° C./min, the glass transition temperature Tg1 is ?20° C. to 20° C., and the glass transition temperature Tg2 is 35° C. to 65° C., wherein the binder resin comprises a polyester skeleton and a ring-containing skeleton molecule at ends thereof, and wherein the binder resin is obtained by block copolymerization of: a polyester skeleton A which includes a structural unit obtained by dehydration condensation of a hydroxycarboxylic acid in a repeating structure; and a skeleton B which does not include a structural unit obtained by dehydration condensation of a hydroxycarboxylic acid in a repeating structure.
    Type: Application
    Filed: December 27, 2012
    Publication date: July 4, 2013
    Inventors: Suzuka Amemori, Masahide Yamada, Yoshihiro Moriya, Taichi Nemoto, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita, Keiji Makabe, Akiyoshi Sabu
  • Publication number: 20130157183
    Abstract: A developer, including a toner including a binder resin comprising a crystalline resin; and a colorant, and a resin carrier comprising a resin; a magnetic particulate material having a magnetic anisotropy, dispersed in the resin, and having a saturated magnetization of from 16 to 30 emu/g, a coercive force of from 15 to 40 kA/m and an average particle diameter not less than 15 ?m and less than 100 ?m.
    Type: Application
    Filed: November 16, 2012
    Publication date: June 20, 2013
    Inventors: Hideyuki Santo, Masahide Yamada, Kazumi Suzuki, Shinya Nakayama, Atsushi Yamamoto, Tatsuya Morita, Shingo Sakashita, Yukiko Nakajima, Keiji Makabe, Daiki Yamashita
  • Publication number: 20130157185
    Abstract: A toner includes a binder resin, a coloring agent, and a releasing agent containing two or more kinds of alkyl monoester compounds having a different number of carbon atoms in a range of from 30 to 50 carbon atoms. The toner has a crystallinity of 10% or more as measured by x-ray diffraction and/or the binder resin is a crystalline resin in an amount of 50% by weight or more of the binder resin. The two or more kinds of alkyl monoester compounds include a component A accounting for the largest amount ranging from 30% by weight to less than 50% by weight of the releasing agent and a component B accounting for the second largest amount ranging from 10% by weight to less than 50% by weight of the releasing agent.
    Type: Application
    Filed: December 5, 2012
    Publication date: June 20, 2013
    Inventors: Shingo SAKASHITA, Hiroshi Yamashita, Masahide Yamada, Shinya Nakayama, Atsushi Yamamoto, Yukiko Nakajima
  • Publication number: 20130149642
    Abstract: To provide a toner, which contains a first binder resin, and a second binder resin, wherein the first binder resin is a block polymer containing at least a polyester skeleton A having, in a repeating structure thereof, a constitutional unit formed by dehydration condensation of hydroxycarboxylic acid, and a skeleton B that does not have, in a repeating structure thereof, a constitutional unit formed by dehydration condensation of hydroxycarboxylic acid, and the first binder resin has glass transition temperature Tg1 and Tg 2 as measured by differential scanning calorimetry at a heating rate of 5° C./min, wherein the Tg1 is ?20° C. to 20° C., and the Tg2 is 35° C. to 65° C., and wherein the second binder resin is a crystalline resin.
    Type: Application
    Filed: November 20, 2012
    Publication date: June 13, 2013
    Inventors: Akiyoshi SABU, Yoshihiro MORIYA, Taichi NEMOTO, Yoshitaka YAMAUCHI, Yukiko NAKAJIMA, Keiji MAKABE, Suzuka AMEMORI, Daiki YAMASHITA, Masahide YAMADA
  • Publication number: 20130065172
    Abstract: A toner including a colorant and a first binder resin is provided. The first binder resin has first and second glass transition points at a temperature Tg1 of ?20 to 20° C. and a temperature Tg2 of 35 to 65° C., respectively, measured by a differential scanning calorimeter at a heating rate of 5° C./min. A ratio h1/h2 of a baseline displacement h1 observed in the first glass transition point to a baseline displacement h2 observed in the second glass transition point is less than 1.0. The first binder resin has a structure in which a first phase is dispersed in a second phase. The first and second phases consist of portions having larger and smaller phase difference values, respectively, than an intermediate value between maximum and minimum phase difference values in a binarized phase image obtained by an atomic force microscope with a tapping mode method.
    Type: Application
    Filed: September 11, 2012
    Publication date: March 14, 2013
    Inventors: Yoshihiro MORIYA, Masahide YAMADA, Taichi NEMOTO, Yukiko NAKAJIMA, Yoshitaka YAMAUCHI, Daiki YAMASHITA, Keiji MAKABE, Akiyoshi SABU, Suzuka AMEMORI
  • Publication number: 20130045442
    Abstract: A toner including a resin particle (C) is provided. The resin particle (C) includes a resin particle (B) and a resin particle (A). The resin particle (B) includes a resin (b). The resin particle (A) or covering layer (P) includes a resin (a). The resin particle (A) or covering layer (P) is adhered to a surface of the resin particle (B). The resin (a) is a polyester resin. The resin (a) has a total acid value of 15 to 36 mgKOH/g. The resin particle (A) or covering layer (P) has a surface acid value of 10 to 27 mgKOH/g.
    Type: Application
    Filed: August 2, 2012
    Publication date: February 21, 2013
    Inventors: Yoshihiro MORIYA, Shinya Nakayama, Atsushi Yamamoto, Hideyuki Santo, Akiyoshi Sabu, Yukiko Nakajima, Daiki Yamashita
  • Publication number: 20120295188
    Abstract: A resin for use in toner is provided. The resin comprises an oligomer segment and a soft segment. The oligomer segment comprises a polyhydroxycarboxylic skeleton and an aromatic diol skeleton.
    Type: Application
    Filed: May 15, 2012
    Publication date: November 22, 2012
    Inventors: Yukiko NAKAJIMA, Masahide YAMADA, Taichi NEMOTO, Yoshihiro MORIYA, Yoshitaka YAMAUCHI, Keiji MAKABE, Daiki YAMASHITA, Akiyoshi SABU
  • Publication number: 20120231383
    Abstract: A resin for toner containing a polyhydroxy carbonate skeleton and a rigid skeleton.
    Type: Application
    Filed: March 7, 2012
    Publication date: September 13, 2012
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hideyuki SANTO, Shinya NAKAYAMA, Atsushi YAMAMOTO, Yoshihiro MORIYA, Akiyoshi SABU, Daisuke ASAHINA, Yoshitaka YAMAUCHI, Taichi NEMOTO, Yukiko NAKAJIMA, Daiki YAMASHITA, Masahide YAMADA, Keiji MAKABE
  • Publication number: 20110281213
    Abstract: A toner containing a binder resin comprising a first binder resin A and a second binder resin B, a coloring agent, and a releasing agent, wherein the first binder resin A is formed by reacting a compound A1 having an active hydrogen group with a resin A2 having a portion reactive with the compound A1 in an organic solvent and the resin A2 is formed by reacting a non-crystalline polyester resin “a” having a polyhydroxy carboxylic acid skeleton in the main chain with a compound having the portion reactive with the compound A1 having an active hydrogen group.
    Type: Application
    Filed: May 9, 2011
    Publication date: November 17, 2011
    Inventors: Shingo SAKASHITA, Shinya Nakayama, Ryota Inoue, Yoshihiro Moriya, Akiyoshi Sabu, Yukiko Nakajima, Daiki Yamashita
  • Publication number: 20110151370
    Abstract: The present invention provides a toner including: a colorant, and a binder resin, wherein the toner is fixed on a recording medium using a fixing liquid containing a softening agent for softening the toner, and wherein a weight average molecular weight of a THF soluble fraction of the toner in a molecular weight distribution measured by gel permeation chromatography (GPC) is 3,000 to 8,300; and a glass transition temperature of the toner measured by differential scanning calorimetry (DSC) is 50° C. to 70° C.
    Type: Application
    Filed: December 20, 2010
    Publication date: June 23, 2011
    Inventors: Yasutada SHITARA, Yohichiroh Watanabe, Yasuo Katano, Shinya Nakayama, Ryota Inoue, Yoshihiro Moriya, Akiyoshi Sabu, Shingo Sakashita, Yukiko Nakajima
  • Publication number: 20110124838
    Abstract: The present invention provides a method for producing a toner, which includes 1) saccharifying paper by at least one of a chemical degradation method and a biochemical degradation method to obtain a sugar-containing solution, 2) subjecting the sugar-containing solution obtained through 1) to lactic acid fermentation to obtain a lactic acid, 3) polymerizing the lactic acid obtained through 2) to obtain a polylactic acid, and 4) producing a toner using the polylactic acid obtained through 3).
    Type: Application
    Filed: November 18, 2010
    Publication date: May 26, 2011
    Inventors: Akihiro Kotsugai, Keiko Osaka, Yoshihiro Moriya, Shingo Sakashita, Yukiko Nakajima, Yoshitaka Yamauchi, Ryota Inoue, Akiyoshi Sabu, Daiki Yamashita
  • Publication number: 20110104608
    Abstract: To provide a toner including: a resin particle (C) containing a first resin (a1), a second resin (a2), and a resin particle (B) to a surface of which the first resin (a1) and the second resin (a2) are attached, wherein the first resin (a1) and the second resin (a2) have mutually different glass transition temperatures, and wherein the resin particle (B) contains a third resin (b) having an amorphous polyhydroxycarboxylic acid skeleton.
    Type: Application
    Filed: August 3, 2010
    Publication date: May 5, 2011
    Inventors: Yukiko NAKAJIMA, Akihiro Kotsugai, Ryota Inoue, Akiyoshi Sabu, Shingo Sakashita, Keiko Osaka
  • Publication number: 20110065036
    Abstract: A toner including: a first binder resin; a colorant; a releasing agent; and a crystalline organic compound, wherein the first binder resin contains an amorphous polyester resin (a) having a polyhydroxycarboxylic acid skeleton derived from optically active monomers in a part of a main chain of the amorphous polyester resin, and the polyhydroxycarboxylic acid skeleton has an optical purity X, calculated on the monomer basis, of 80% or less, and the optical purity X is determined from the equation, Optical Purity X (%)=|X (L-form)?X (D-form)| wherein the crystalline organic compound is any one of a crystalline polyester resin (b) and a crystalline low molecular compound having a melting point of 60° C. to 100° C., and being selected from a group consisting of fatty acid having 16 to 24 carbon atoms, alcohol having 16 to 24 carbon atoms, a fatty acid ester compound, and aliphatic carboxylic acid amide.
    Type: Application
    Filed: September 9, 2010
    Publication date: March 17, 2011
    Inventors: Ryota Inoue, Akihiro Kotsugai, Yoshihiro Moriya, Akiyoshi Sabu, Shingo Sakashita, Keiko Osaka, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita
  • Publication number: 20100330489
    Abstract: An electrostatic image developing toner including a toner particle (C), wherein the toner particle (C) has a structure in which a resin particle (A) containing at least a first resin (a) or a coated film (P) containing the first resin (a) is attached to a surface of a resin-containing particle (B) containing a second resin (b), and wherein the resin (b) includes a polyhydroxycarboxylic acid skeleton, and the resin (a) is a polyester resin containing a polybasic acid and a polyhydric alcohol.
    Type: Application
    Filed: June 28, 2010
    Publication date: December 30, 2010
    Inventors: Ryota INOUE, Akihiro Kotsugai, Akiyoshi Sabu, Shingo Sakashita, Yukiko Nakajima, Keiko Osaka
  • Publication number: 20100216068
    Abstract: A toner including a colorant, a thermoplastic resin (a) comprising an amorphous polyester resin having a main chain having a polyhydroxycarboxylic acid skeleton, and a thermoplastic resin (b) is provided. The toner is manufactured by a method including mixing the colorant with the thermoplastic resin (a) to prepare a preliminary mixture, and mixing the preliminary mixture with the thermoplastic resin (b).
    Type: Application
    Filed: February 26, 2010
    Publication date: August 26, 2010
    Inventors: Akihiro KOTSUGAI, Toyoshi Sawada, Ryota Inoue, Akiyoshi Sabu, Shingo Sakashita, Keiko Osaka, Yukiko Nakajima
  • Publication number: 20100183967
    Abstract: A toner including a binder resin comprising a resin (a) comprising a polyhydroxycarboxylic acid skeleton formed from an optically-active monomer. The polyhydroxycarboxylic acid skeleton has a weight average molecular weight of from 7,000 to 60,000. The binder resin comprises the polyhydroxycarboxylic acid skeleton in an amount of from 10 to 90% by weight. The optical purity X (%) of the polyhydroxycarboxylic acid skeleton represented by the following formula is 80% or less: X(%)=|X(L-isomer)?X(D-isomer)| wherein X(L-isomer) and X(D-isomer) represent molar ratio (%) of L-isomer and D-isomer of the optically-active monomer, respectively.
    Type: Application
    Filed: December 30, 2009
    Publication date: July 22, 2010
    Inventors: Akiyoshi Sabu, Akihiro Kotsugai, Ryota Inoue, Keiko Osaka, Shingo Sakashita, Yukiko Nakajima, Satoshi Mochizuki