Patents by Inventor Ryohta Inoue

Ryohta Inoue 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: 7374848
    Abstract: A toner including a binder; a colorant; and a wax, wherein the binder includes a polyester resin; and a reaction product of a polymer having a group capable of reacting with an active hydrogen with a compound having an active hydrogen, wherein the polyester resin includes tetrahydrofuran(THF)-soluble resin components in an amount of from 50 to 85% by weight; and chloroform-insoluble components in an amount of from 0 to 30% by weight, and wherein the toner satisfies the following relationship (1): 5% by weight<(C1-C2)<60% by weight ??(1) wherein C1 represents a content of chloroform-insoluble components in the toner in units of % by weight and C2 represents a content of the colorant therein in units of % by weight.
    Type: Grant
    Filed: June 22, 2004
    Date of Patent: May 20, 2008
    Assignee: Ricoh Company, Limited
    Inventors: Sonoh Matsuoka, Ryohta Inoue, Masahiro Ohki, Takeshi Takada, Chiaki Tanaka, Naohiro Watanabe, Masahide Yamada
  • Patent number: 7348121
    Abstract: A toner including toner particles comprising a binder resin; and at least two kinds of particulate resins which are located on at least a surface of the toner particles, wherein the toner satisfies at least one of the following relationships (TgA?TgB)?20° C., wherein TgA and TgB represent glass transition temperatures (Tg) of a particulate resin (A) having a highest Tg and a particulate resin (B) having a lowest Tg among the at least two kinds of particulate resins, respectively; and 100,000?Mwc?6,000,000 and 8,000?Mwd?800,000, wherein Mwc and Mwd represent weight average molecular weights (Mw) of a particulate resin (C) having a highest Mw and a particulate resin (D) having a lowest Mw among the at least two kinds of particulate resins, respectively, wherein Mwc>Mwd.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: March 25, 2008
    Assignee: Ricoh Company Limited
    Inventors: Ryohta Inoue, Naohiro Watanabe, Masahide Yamada, Sonoh Matsuoka, Chiaki Tanaka, Takeshi Takada, Masahiro Ohki, Akinori Saitoh
  • Patent number: 7348117
    Abstract: A toner including toner particles comprising a binder resin; and at least two kinds of particulate resins which are located on at least a surface of the toner particles, wherein the toner satisfies at least one of the following relationships (TgA-TgB)?20° C., wherein TgA and TgB represent glass transition temperatures (Tg) of a particulate resin (A) having a highest Tg and a particulate resin (B) having a lowest Tg among the at least two kinds of particulate resins, respectively; and 100,000?Mwc?6,000,000 and 8,000?Mwd?800,000, wherein Mwc and Mwd represent weight average molecular weights (Mw) of a particulate resin (C) having a highest Mw and a particulate resin (D) having a lowest Mw among the at least two kinds of particulate resins, respectively, wherein Mwc>Mwd.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: March 25, 2008
    Assignee: Ricoh Company Limited
    Inventors: Ryohta Inoue, Naohiro Watanabe, Masahide Yamada, Sonoh Matsuoka, Chiaki Tanaka, Takeshi Takada, Masahiro Ohki, Akinori Saitoh
  • Publication number: 20070141506
    Abstract: A toner including toner particles comprising a binder resin; and at least two kinds of particulate resins which are located on at least a surface of the toner particles, wherein the toner satisfies at least one of the following relationships (TgA?TgB)?20° C., wherein TgA and TgB represent glass transition temperatures (Tg) of a particulate resin (A) having a highest Tg and a particulate resin (B) having a lowest Tg among the at least two kinds of particulate resins, respectively; and 100,000?Mwc?6,000,000 and 8,000?Mwd?800,000, wherein Mwc and Mwd represent weight average molecular weights (Mw) of a particulate resin (C) having a highest Mw and a particulate resin (D) having a lowest Mw among the at least two kinds of particulate resins, respectively, wherein Mwc>Mwd.
    Type: Application
    Filed: February 2, 2007
    Publication date: June 21, 2007
    Inventors: Ryohta INOUE, Naohiro Watanabe, Masahide Yamada, Sonoh Matsuoka, Chiaki Tanaka, Takeshi Takada, Masahiro Ohki, Akinori Saitoh
  • Patent number: 7208256
    Abstract: A toner for image formation is provided, which is produced by dispersing in an aqueous solvent a toner composition which includes a composition thermally soluble in an organic solvent and a coloring agent, thereby forming toner particles, wherein the thermally soluble composition includes (a) a polyester having an acid value and (b) a metal alcolate and/a metal chelate compound. The toner is capable of attaining image fixing at a sufficiently low image fixing temperature and a sufficiently broad image fixing temperature range for use in practice. Furthermore, toner containers such as a toner cartridge and a process cartridge are provided, which are loaded with the toner. Such toner containers can be detachably mounted on an image forming apparatus.
    Type: Grant
    Filed: March 18, 2004
    Date of Patent: April 24, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Chiaki Tanaka, Naohiro Watanabe, Takeshi Takada, Ryohta Inoue
  • Publication number: 20050031980
    Abstract: A toner including toner particles comprising a binder resin; and at least two kinds of particulate resins which are located on at least a surface of the toner particles, wherein the toner satisfies at least one of the following relationships (TgA?TgB)?20° C., wherein TgA and TgB represent glass transition temperatures (Tg) of a particulate resin (A) having a highest Tg and a particulate resin (B) having a lowest Tg among the at least two kinds of particulate resins, respectively; and 100,000?Mwc?6,000,000 and 8,000?Mwd?800,000, wherein Mwc and Mwd represent weight average molecular weights (Mw) of a particulate resin (C) having a highest Mw and a particulate resin (D) having a lowest Mw among the at least two kinds of particulate resins, respectively, wherein Mwc>Mwd.
    Type: Application
    Filed: August 4, 2004
    Publication date: February 10, 2005
    Inventors: Ryohta Inoue, Naohiro Watanabe, Masahide Yamada, Sonoh Matsuoka, Chiaki Tanaka, Takeshi Takada, Masahiro Ohki, Akinori Saitoh
  • Publication number: 20050026066
    Abstract: A toner for image formation is provided, which is produced by dispersing in an aqueous solvent a toner composition which includes a composition thermally soluble in an organic solvent and a coloring agent, thereby forming toner particles, wherein the thermally soluble composition includes (a) a polyester having an acid value and (b) a metal alcolate and/a metal chelate compound. The toner is capable of attaining image fixing at a sufficiently low image fixing temperature and a sufficiently broad image fixing temperature range for use in practice. Furthermore, toner containers such as a toner cartridge and a process cartridge are provided, which are loaded with the toner. Such toner containers can be detachably mounted on an image forming apparatus.
    Type: Application
    Filed: March 18, 2004
    Publication date: February 3, 2005
    Inventors: Chiaki Tanaka, Naohiro Watanabe, Takeshi Takada, Ryohta Inoue
  • Publication number: 20040265721
    Abstract: A toner including a binder; a colorant; and a wax, wherein the binder includes a polyester resin; and a reaction product of a polymer having a group capable of reacting with an active hydrogen with a compound having an active hydrogen, wherein the polyester resin includes tetrahydrofuran(THF)-soluble resin components in an amount of from 50 to 85% by weight; and chloroform-insoluble components in an amount of from 0 to 30% by weight, and wherein the toner satisfies the following relationship (1):
    Type: Application
    Filed: June 22, 2004
    Publication date: December 30, 2004
    Inventors: Sonoh Matsuoka, Ryohta Inoue, Masahiro Ohki, Takeshi Takada, Chiaki Tanaka, Naohiro Watanabe, Masahide Yamada