Patents by Inventor Masahide Yamada

Masahide Yamada 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: 8795939
    Abstract: A toner, including a lactone compound having not less than 14-membered rings; and a resin including a crystalline polyester unit.
    Type: Grant
    Filed: October 1, 2012
    Date of Patent: August 5, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Yamamoto, Shinya Nakayama, Masahide Yamada, Hideyuki Santo, Suzuka Amemori
  • Patent number: 8795940
    Abstract: To provide a toner, including at least: a non-crystalline polyester resin; and a crystalline polyester resin, wherein the toner has a glass transition temperature in a first heating Tg1st and a glass transition temperature in a second heating Tg2nd, and a difference between Tg1st and Tg2nd (Tg1st-Tg2nd) is 10° C. or greater, and wherein the crystalline polyester resin is a modified crystalline polyester resin having a urethane skeleton or a urea skeleton, or both thereof.
    Type: Grant
    Filed: November 26, 2012
    Date of Patent: August 5, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Tsuyoshi Sugimoto, Hiroshi Yamashita, Daisuke Asahina, Rintaro Takahashi, Masahide Yamada, Shinya Nakayama, Atsushi Yamamoto, Shingo Sakashita
  • Patent number: 8735040
    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: Grant
    Filed: December 27, 2012
    Date of Patent: May 27, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Suzuka Amemori, Masahide Yamada, Yoshihiro Moriya, Taichi Nemoto, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita, Keiji Makabe, Akiyoshi Sabu
  • Patent number: 8685604
    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: Grant
    Filed: September 11, 2012
    Date of Patent: April 1, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Moriya, Masahide Yamada, Taichi Nemoto, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita, Keiji Makabe, Akiyoshi Sabu, Suzuka Amemori
  • Publication number: 20140080051
    Abstract: To provide a toner (X), which contains toner particles, each toner particle contains: a core phase (Q) containing a crystalline resin (A); and a shell phase (S) provided on a surface of the core phase (Q), where the shell phase (S) contains a crystalline polyurethane resin (B), wherein maximum peak temperature (Ta) of heat of melting of the crystalline resin (A) is 40° C. to 70° C., and maximum peak temperature (Tu) of heat of melting of the crystalline polyurethane resin (B) is 50° C. to 90° C.
    Type: Application
    Filed: September 17, 2013
    Publication date: March 20, 2014
    Inventors: Toyoshi SAWADA, Masahide YAMADA, Atsushi YAMAMOTO, Tatsuya MORITA, Satoyuki SEKIGUCHI, Keiji MAKABE, Kousuke NAGATA
  • Publication number: 20140065534
    Abstract: A toner, including: a crystalline resin containing a urethane bond, a urea bond, or both thereof; and a compound represented by the following General Formula (1), wherein an amount of the compound represented by the General Formula (1) is 0.01% by mass to 0.25% by mass: CnH2n+1R??General Formula (1) where n is 8 to 22 and R is COOH, NH2 or OH.
    Type: Application
    Filed: August 29, 2013
    Publication date: March 6, 2014
    Inventors: Suzuka AMEMORI, Atsushi Yamamoto, Masahide Yamada, Yukiko Nakajima, Shinya Nakayama, Hideyuki Santo
  • Publication number: 20140051019
    Abstract: Toner contains a binder resin containing a crystalline resin having a urethane and/or urea bonding; and a colorant, wherein in a diffraction spectrum of the toner as measured by an X-ray diffraction instrument, a ratio {C/(C+A)} of an integral intensity C of the spectrum derived from the crystalline structure to an integral intensity A of the spectrum derived from the non-crystalline structure is 0.12 or greater, wherein the toner satisfies the following relation 1: T1?T2?30° C. (Relation 1), where T1 represents the maximum endothermic peak in the first temperature rising from 0° C. to 100° C. at the temperature rising rate of 10° C./min and T2 represents the maximum exothermic peak in the first temperature falling from 100° C. to 0° C. at the temperature falling rate of 10° C./min as T1 and T2 are measured by diffraction scanning calorimetry (DSC).
    Type: Application
    Filed: August 5, 2013
    Publication date: February 20, 2014
    Inventors: Satoyuki Sekiguchi, Hiroshi Yamashita, Minoru Masuda, Susumu Chiba, Tatsuya Morita, Atsushi Yamamoto, Shinya Nakayama, Masahide Yamada, Kohsuke Nagata, Keiji Makabe, Toyoshi Sawada
  • Patent number: 8603715
    Abstract: A toner including a core particle and projections at a surface of the core particle is provided. The core particle includes a binder resin and a colorant. The binder resin includes a crystalline resin as a major component. Each of the projections consists of a fine resin particle. An average length of long sides of the projections is not less than 0.15 ?m and less than 0.5 ?m. A standard deviation of lengths of the long sides of the projections is 0.2 or less. A surface coverage of the toner with the projections is within a range of 30 to 90%.
    Type: Grant
    Filed: October 19, 2012
    Date of Patent: December 10, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Suzuka Amemori, Atsushi Yamamoto, Masahide Yamada, Shinya Nakayama, Hideyuki Santo, Daiki Yamashita
  • Patent number: 8580476
    Abstract: A toner for developing an electrostatic image is provided. The toner includes at least a binder resin; a colorant; and a particulate release agent. The particulate release agent is prepared by heating the release agent to a temperature not lower than a melting point of the release agent to melt the release agent, dissolving the melted release agent in a supercritical fluid or a sub-critical fluid, and feeding the solution into a liquid so that the solution is depressurized and the particulate release agent is formed in the liquid.
    Type: Grant
    Filed: March 14, 2011
    Date of Patent: November 12, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahide Yamada, Chiaki Tanaka, Masahiro Kawamoto, Tatsunori Kamiyama, Satoshi Izumi
  • Publication number: 20130260298
    Abstract: A toner including: a binder resin; and a colorant, wherein the toner is obtained by dispersing or emulsifying an oil phase in an aqueous solvent containing an organic sulfonic acid salt and an inorganic salt, the oil phase including the binder resin and the colorant dissolved or dispersed in an organic solvent, wherein the binder resin comprises a crystalline resin in an amount of 50% by mass or more relative to the binder resin, and wherein the toner has an average circularity of 0.980 or less.
    Type: Application
    Filed: March 8, 2013
    Publication date: October 3, 2013
    Inventors: Suzuka AMEMORI, Masahide YAMADA, Shinya NAKAYAMA, Yukiko NAKAJIMA
  • Publication number: 20130252158
    Abstract: An electrophotographic toner, including: a binder resin; a colorant; and an organically-modified layered inorganic mineral, wherein the binder resin contains 50% by mass or more of a crystalline resin relative to the binder resin, and the crystalline resin contains a resin having a sulfonic acid group, and wherein an amount of the sulfonic acid group is 0.1% by mass to 2.0% by mass relative to the resin having the sulfonic acid group.
    Type: Application
    Filed: March 8, 2013
    Publication date: September 26, 2013
    Inventors: Masahide YAMADA, Shinya NAKAYAMA, Atsushi YAMAMOTO, Hideyuki SANTO, Shingo SAKASHITA, Yukiko NAKAJIMA, Suzuka AMEMORI, Akiyoshi SABU
  • Publication number: 20130244154
    Abstract: Toner containing a binder resin that contains at least one kind of resin having a crystalline polyester unit as its main component and a releasing agent containing a straight-chain mono ester having 48 or more carbon atoms accounting for 40% by weight or more of the releasing agent.
    Type: Application
    Filed: March 4, 2013
    Publication date: September 19, 2013
    Inventors: Atsushi YAMAMOTO, Shinya NAKAYAMA, Hideyuki SANTO, Suzuka AMEMORI, Shingo SAKASHITA, Masahide YAMADA
  • Publication number: 20130244167
    Abstract: A toner including a binder resin having a glass transition temperature (Tg) observed at least at one point from 25 to 65° C. in a differential scanning calorimeter at a rate of temperature increase of 5° C./min, wherein the toner has a structure in which a structure appearing as a high phase difference image is dispersed in a structure appearing as a low phase difference image in a two-dimensional phase difference image observed by tapping mode AFM, and an X-ray diffraction chart in which a peak originated from an crystalline resin is observed in a range of a diffraction angle 2? of from 20 to 25°, and wherein a ratio (I1/I2) of an intensity of the peak originated from an crystalline resin to an intensity (I2) of a halo originated from an amorphous composition is from 0.2 to 1.
    Type: Application
    Filed: January 31, 2013
    Publication date: September 19, 2013
    Inventors: Daiki YAMASHITA, Yoshihiro Moriya, Yukiko Nakajima, Taichi Nemoto, Yoshitaka Yamauchi, Keiji Makabe, Masahide Yamada, Suzuka Amemori
  • 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: 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
  • Patent number: 8492063
    Abstract: A method of manufacturing a toner including forming a wax liquid dispersion in which a wax is dispersed in an organic solvent (A1), mixing an organic layer including the wax liquid dispersion, a binder resin and an organic solvent (A) to form an oil phase and dispersing and emulsifying the oil phase in an aqueous medium to obtain an emulsified liquid dispersion, wherein the aspect ratio average of the wax in the wax liquid dispersion is from 0.3 to 0.7 and the toner includes toner particles satisfying the following relationship (1) in an amount of 20% by number or smaller based on all toner particles: 0.5<D2/D1, relationship (1), where D1 represents the major diameter (D1) of the toner and D2 represents the major diameter of the wax.
    Type: Grant
    Filed: November 28, 2008
    Date of Patent: July 23, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Junichi Awamura, Akinori Saitoh, Masahide Yamada, Osamu Uchinokura, Tomomi Suzuki
  • 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: 20130157184
    Abstract: To provide a toner, including at least: a non-crystalline polyester resin; and a crystalline polyester resin, wherein the toner has a glass transition temperature in a first heating Tg1st and a glass transition temperature in a second heating Tg2nd, and a difference between Tg1st and Tg2nd (Tg1st?Tg2nd) is 10° C. or greater, and wherein the crystalline polyester resin is a modified crystalline polyester resin having a urethane skeleton or a urea skeleton, or both thereof.
    Type: Application
    Filed: November 26, 2012
    Publication date: June 20, 2013
    Inventors: Tsuyoshi SUGIMOTO, Hiroshi Yamashita, Daisuke Asahina, Rintaro Takahashi, Masahide Yamada, Shinya Nakayama, Atsushi Yamamoto, Shingo Sakashita
  • 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