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).

  • 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: 20130115550
    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: Application
    Filed: October 19, 2012
    Publication date: May 9, 2013
    Inventors: Suzuka Amemori, Atsushi Yamamoto, Masahide Yamada, Shinya Nakayama, Hideyuki Santo, Daiki Yamashita
  • Publication number: 20130108950
    Abstract: A toner, including a lactone compound having not less than 14-membered rings; and a resin including a crystalline polyester unit.
    Type: Application
    Filed: October 1, 2012
    Publication date: May 2, 2013
    Inventors: Atsushi Yamamoto, Shinya Nakayama, Masahide Yamada, Hideyuki Santo, Suzuka Amemori
  • Publication number: 20130095422
    Abstract: A toner, including a crystalline resin as a binder resin, wherein the toner comprises a THF-soluble component in a weight-average molecular weight not less than 20,000, and has a 50% wettability not less than 20% by volume when subjected to a methanol wettability test.
    Type: Application
    Filed: October 1, 2012
    Publication date: April 18, 2013
    Inventors: Atsushi YAMAMOTO, Shinya Nakayama, Masahide Yamada, Hideyuki Santo, Daiki Yamashita, Ryota Inoue
  • Publication number: 20130078563
    Abstract: A toner includes a coloring agent, a binder resin comprising a crystalline resin having a urethane skeleton and/or urea skeleton, and a releasing agent (a microcrystalline wax). A development agent, a process cartridge, and an image forming apparatus employ the toner to form images on recording media electrophotographically.
    Type: Application
    Filed: September 10, 2012
    Publication date: March 28, 2013
    Inventors: Shinya Nakayama, Atsushi Yamamoto, Hideyuki Santo, Daiki Yamashita, Suzuka Amemori, 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: 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: 20120282000
    Abstract: To provide a toner for electrophotography, which contains a binder resin, a colorant, and an organic-modified layered inorganic mineral, wherein the binder resin contains a crystalline resin in an amount of 50% by mass or greater, and wherein the organic-modified layered inorganic mineral is an organic-modified layered inorganic mineral in which at least part of ions present between layers of a layered inorganic mineral are modified with organic ions.
    Type: Application
    Filed: April 27, 2012
    Publication date: November 8, 2012
    Inventors: Shinya Nakayama, Atsushi Yamamoto, Masahide Yamada, Hideyuki Santo, Daiki Yamashita, Suzuka Amemori
  • 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
  • Patent number: 8192911
    Abstract: A method of manufacturing a toner including dispersing a binder resin, a coloring agent and a releasing agent in an organic solvent to obtain an oil phase; dispersing the oil phase in an aqueous medium with a shearing force to obtain a dispersion emulsion; wherein the shearing force is made by a screen or vessel that is situated around a rotor, the screen spinning in a direction opposite to the direction that the rotor spins. Toner produced. Method of using the toner.
    Type: Grant
    Filed: May 8, 2009
    Date of Patent: June 5, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Junichi Awamura, Akinori Saitoh, Osamu Uchinokura, Masahide Yamada, Tomomi Suzuki
  • Patent number: 8178276
    Abstract: A method of manufacturing a toner including granulating mother toner particles in an aqueous medium to obtain a slurry containing the mother toner particles and adjusting a size distribution of the mother toner particles by screening coarse mother toner particles from the slurry with a screen to obtain the toner containing mother toner particulates.
    Type: Grant
    Filed: March 6, 2009
    Date of Patent: May 15, 2012
    Assignee: Ricoh Company Limited
    Inventors: Osamu Uchinokura, Akinori Saitoh, Junichi Awamura, Masahide Yamada, Hiroshi Yamada
  • Patent number: 8137883
    Abstract: A toner is provided including a binder resin and a wax having primarily C—H and C—C bonds, and having a melting point of 50 to 90° C., wherein the wax is present in a surface portion of the toner in an amount of from 0.1 to 4.0% by weight, wherein the amount of the wax is determined by Fourier transform infrared spectroscopy attenuated total reflectance (FTIR-ATR); and the use of the toner in an image forming method, image forming apparatus, developer and toner cartridge containing the toner.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: March 20, 2012
    Assignee: Ricoh Company Limited
    Inventors: Ryota Inoue, Shigeru Emoto, Naohiro Watanabe, Masahide Yamada, Akinori Saitoh, Masahiro Ohki, Tsunemi Sugiyama, Shinichi Wakamatsu, Takayuki Yoshii, Eiji Sawamura
  • Patent number: 8124308
    Abstract: Toner and a developer which are excellent in cleaning property and fixing property at low temperature, and capable of forming images with high quality are provided, along with a method for their production. A toner producing method involves dispersing and/or emulsifying an oil phase or a monomer phase containing a toner composition and/or a toner composition precursor in a water-based medium to granulate, wherein the toner has an average circularity of 0.925 to 0.970, and the toner composition and/or the toner composition precursor has a layered inorganic material in which at least a part of interlayer ions in the layered inorganic material has been exchanged with organic ions.
    Type: Grant
    Filed: December 13, 2010
    Date of Patent: February 28, 2012
    Assignee: Ricoh Company. Ltd.
    Inventors: Naohiro Watanabe, Shigeru Emoto, Yohichiroh Watanabe, Masahide Yamada, Tsunemi Sugiyama, Masahiro Ohki, Akinori Saitoh, Ryota Inoue, Osamu Uchinokura, Junichi Awamura
  • Patent number: 8034524
    Abstract: A toner satisfying at least one of the following relationships: 10° C.<(T1?T2)<60° C. and 0<Q2/Q1<? wherein T1 represents a glass transition temperature of the toner and Q1 represents an endothermic quantity at a melting point thereof before melting when heated from ?20° C. to 150° C. at a heating speed of 10° C./min, and T2 represents a glass transition temperature thereof and Q2 represents a an endothermic quantity at a melting point thereof after melting after heated from ?20° C. to 150° C. at a heating speed of 10° C./min, cooled to ?20° C. at a cooling speed of 10° C./min and heated again at a heating speed of 10° C./min.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: October 11, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Inoue, Sonoh Matsuoka, Chiaki Tanaka, Naohiro Watanabe, Masahide Yamada, Masahiro Ohki, Akinori Saitoh
  • Publication number: 20110236818
    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: Application
    Filed: March 14, 2011
    Publication date: September 29, 2011
    Inventors: Masahide YAMADA, Chiaki TANAKA, Masahiro KAWAMOTO, Tatsunori KAMIYAMA, Satoshi IZUMI
  • Patent number: 8026031
    Abstract: Toner and a developer which are excellent in cleaning property and fixing property at low temperature, and capable of forming images with high quality are provided. A toner prepared by dispersing and/or emulsifying an oil phase or a monomer phase comprising a toner composition and/or a toner composition precursor in a water-based medium to granulate, wherein the toner has an average circularity of 0.925 to 0.970, and the toner composition and/or the toner composition precursor has a layered inorganic material in which at least a part of interlayer ions in the layered inorganic material has been exchanged with organic ions.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: September 27, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Naohiro Watanabe, Shigeru Emoto, Yohichiroh Watanabe, Masahide Yamada, Tsunemi Sugiyama, Masahiro Ohki, Akinori Saitoh, Ryota Inoue, Osamu Uchinokura, Junichi Awamura
  • Publication number: 20110223530
    Abstract: A toner is provided including a binder resin and a wax having primarily C—H and C—C bonds, and having a melting point of 50 to 90° C., wherein the wax is present in a surface portion of the toner in an amount of from 0.1 to 4.0% by weight, wherein the amount of the wax is determined by Fourier transform infrared spectroscopy attenuated total reflectance (FTIR-ATR); and the use of the toner in an image forming method, image forming apparatus, developer and toner cartridge containing the toner.
    Type: Application
    Filed: May 20, 2011
    Publication date: September 15, 2011
    Inventors: Ryota Inoue, Shigeru Emoto, Naohiro Watanabe, Masahide Yamada, Akinori Saitoh, Masahiro Ohki, Tsunemi Sugiyama, Shinichi Wakamatsu, Takayuki Yoshii, Eiji Sawamura
  • Patent number: 8007977
    Abstract: A toner satisfying at least one of the following relationships: 10° C.<(T1?T2)<60° C. and 0<Q2/Q1<2/3 wherein T1 represents a glass transition temperature of the toner and Q1 represents an endothermic quantity at a melting point thereof before melting when heated from ?20° C. to 150° C. at a heating speed of 10° C./min, and T2 represents a glass transition temperature thereof and Q2 represents a an endothermic quantity at a melting point thereof after melting after heated from ?20° C. to 150° C. at a heating speed of 10° C./min, cooled to ?20° C. at a cooling speed of 10° C./min and heated again at a heating speed of 10° C./min.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: August 30, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Inoue, Sonoh Matsuoka, Chiaki Tanaka, Naohiro Watanabe, Masahide Yamada, Masahiro Ohki, Akinori Saitoh
  • Publication number: 20110200929
    Abstract: The present invention provides an electrostatic image developing toner capable of improving the dispersibility of wax in the toner and superior in offset resistance and in storageability (heat-resistant storageability) at high temperatures, and a two-component developer which uses this electrostatic image developing toner. The electrostatic image developing toner includes: a binder resin, a colorant, and a release agent, wherein the binder resin contains a polyester resin, and a block copolymer which has a polyolefin backbone unit.
    Type: Application
    Filed: October 23, 2009
    Publication date: August 18, 2011
    Inventors: Toshihiko Karato, Masahide Yamada, Junichi Awamura, Tomomi Suzuki