Patents by Inventor Takeshi Takada

Takeshi Takada 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: 20080032226
    Abstract: An improved toner comprises a binder resin comprising a urea-modified polyester resin; a colorant master batch comprising a colorant; a resin; and a pigment dispersant. The toner is prepared by a method comprising dissolving or dispersing toner compositions including a modified polyester resin capable of forming the urea-modified polyester resin and the colorant master batch in an organic solvent to provide a liquid; dispersing the liquid in an aqueous medium including resin fine particles while reacting the modified polyester resin with at least one of a crosslinker and an elongation agent to provide particles; and washing the particles after removing the organic solvent therefrom.
    Type: Application
    Filed: October 8, 2007
    Publication date: February 7, 2008
    Inventors: Tsunemi Sugiyama, Hiroshi Yamashita, Yohichiroh Watanabe, Takuya Saito, Takeshi Takada, Masanori Suzuki
  • Patent number: 7314693
    Abstract: The present invention relates to an electrophotographic photoconductor comprising a photoconductive layer, a protective layer, and a conductive support, wherein the protective layer is disposed as the outermost layer of the photoconductive layer, and 20% by volume to 60% by volume of fine particles of fluorine-contained resin and at least one compound selected from amine aromatic compounds and hydroxy aromatic compounds are incorporated into the protective layer. According to the present invention, high durability may be achieved, image degradation such as lags may be controlled from the increase of residual potential and decrease of charging, and high quality images may be formed stably even after the prolonged and repeated usage. The present invention also relates to an electrophotographic process, an electrophotographic apparatus and a process cartridge for the electrophotographic apparatus which utilize the electrophotographic photoconductor respectively.
    Type: Grant
    Filed: September 13, 2004
    Date of Patent: January 1, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Takaaki Ikegami, Shinji Nohsho, Eiji Kurimoto, Hidetoshi Kami, Akihiro Sugino, Yasuyuki Yamashita, Hideo Nakamori, Takeshi Takada
  • Patent number: 7306887
    Abstract: A toner is prepared by dissolving and/or dispersing a modified polyester resin in an organic solvent to yield a solution or dispersion, the modified polyester resin being reactive with a compound having an active hydrogen group, mixing the solution or dispersion with an aqueous medium containing resin particles, and subjecting the modified polyester resin to crosslinking and/or elongation in the aqueous medium. The binder resin further includes a crystalline polyester resin in addition to the modified polyester resin.
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: December 11, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Chiaki Tanaka, Takeshi Takada, Naohiro Watanabe
  • Patent number: 7294442
    Abstract: A toner for developing an electrostatic image having a good combination of hot offset resistance and low temperature fixability. The toner includes (1) a resin having at least one group that can react with a compound having an active hydrogen in an amount of 2 pieces per molecule of the resin, and a colorant. The toner satisfies the following relationship: 3?G=R?Rideal?20, where G represents a ratio of a weight of components other than the colorant and the resin that are insoluble in the organic solvent to total weight of the toner, R represents a weight ratio of components included in the toner that are insoluble in the organic solvent to the total weight of the toner, and Rideal represents an ideal weight ratio of the colorant and the resin, which is calculated from a formula of the toner.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: November 13, 2007
    Assignee: Ricoh Company. Ltd.
    Inventors: Takeshi Takada, Chiaki Tanaka, Naohiro Watanabe
  • Patent number: 7284690
    Abstract: A processed article is provided with a plurality of IDs having the same information for machine reading but difference to be confirmed visually. The information such as the production lot number which is read from the plurality of IDs by the reading device is the same, but these plurality of IDs are different in external appearance, for example in size or color. By corresponding such difference of the plurality of IDs in the external appearance to the positional information in the processing apparatus for the article, new information can be added to the ID without introducing a new ID printer or a reading device. A prompt measure to a trouble in production is made possible based on the information such as the position of the article. Also the defective processed article can be easily selected, thereby improving the production yield and achieving a cost reduction.
    Type: Grant
    Filed: July 21, 2005
    Date of Patent: October 23, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takeshi Takada, Toshihiko Mimura, Naoto Okada
  • Patent number: 7282635
    Abstract: A solar battery module can be constituted without connecting a plurality of bypass diodes, increasing the volume of potting, or reducing the area of a solar battery cell, so that the problems such as an increase in size of a terminal box, an increase in fabrication cost or a drop in mass productivity are overcome. A terminal box constituting an output section of a solar battery module, includes: a box body housing a circuit constituting section constituted by terminal boards, a bypass diode, and the like; and a box cover having a double structure of an inner cover made of a metal material and an outer cover made of a weather-resistant resin. The box body has an open side opposite to its attachment face, and includes a portion housing a charging section of the circuit constituting section apart from an outer wall structure of the box body. The box body is formed to have a box structure made of a weather-resistant resin. The open side of the box structure is covered with the box cover.
    Type: Grant
    Filed: December 16, 2003
    Date of Patent: October 16, 2007
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Keiichiro Utsunomiya, Takeshi Takada, Naoki Ito, Masayoshi Suzuki
  • Publication number: 20070231733
    Abstract: An image forming apparatus at least containing an electrophotographic photoconductor, a latent electrostatic image forming unit, a developing unit, a transferring unit, and a fixing unit, wherein a glass transition temperature of an outermost layer of the electrophotographic photoconductor is 100° C. or more, wherein the toner is obtained by dissolving and/or dispersing the toner material containing at least an active hydrogen group-containing compound and a polymer reactive with the active hydrogen group-containing compound in an organic solvent to form a solution and/or a dispersion, emulsifying and/or dispersing the solution and/or the dispersion in an aqueous medium containing resin fine particles, allowing the active hydrogen group-containing compound and the polymer reactive with the active hydrogen group-containing compound to react in the aqueous medium, and removing the organic solvent, wherein a glass transition temperature of the resin fine particles is 65° C. to 85° C.
    Type: Application
    Filed: April 3, 2007
    Publication date: October 4, 2007
    Inventors: Takeshi Takada, Takaaki Ikegami
  • Patent number: 7235338
    Abstract: A toner prepared by a method of dissolving or dispersing toner constituents comprising a modified resin capable of reacting with an active hydrogen and a colorant which is a black metallic material to prepare a solution or a dispersion; and reacting the solution or dispersion with at least one of a crosslinking agent and an elongation agent in an aqueous medium including a resin particulate material.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: June 26, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Takada, Masahiro Ohki, Toyoshi Sawada, Keiko Shiraishi, Masashi Nagayama
  • 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
  • Publication number: 20070117033
    Abstract: An electrostatic latent image bearing member is provided including a substrate and a photosensitive layer located overlying the substrate, wherein the outermost layer of the electrostatic latent image bearing member includes a cross-linked resin formed from a cross-linking reaction between a charge transport polyol having a specific formula and an isocyanate compound; and the use of the electrostatic latent image bearing member in an image forming apparatus, a process cartridge, and an image forming method.
    Type: Application
    Filed: November 21, 2006
    Publication date: May 24, 2007
    Inventors: Akihiro SUGINO, Takaaki Ikegami, Takeshi Takada, Kazukiyo Nagai
  • Patent number: 7212777
    Abstract: An image forming apparatus including an image bearing member to bear a latent electrostatic image, an irradiation device and developing device to develop a toner latent electrostatic image on the image bearing member, a cleaning blade to remove toner particles remaining on the image bearing member, and a transfer device to transfer the toner image formed on the image bearing member to a recording material. The image forming apparatus satisfies relationships (1) and (2): (1) 0.10< or =Dm3/V< or =3.41, wherein Dm represents a weight average particle diameter of the toner and V represents a circumference velocity of the image bearing member; and (2) Tave< or =1.40 kgf·cm, wherein Tave represents the average of a torque T of the image bearing member when the torque is measured for 15 seconds while the cleaning blade is in contact with the image bearing member.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: May 1, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Takada, Takaaki Ikegami, Akihiro Sugino
  • 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: 20070059618
    Abstract: An object of the present invention is to provide an image forming apparatus containing an electrophotographic photoconductor, a charging unit, an exposing unit, a developing unit, a transfer unit and a cleaning unit, wherein the electrophotographic photoconductor contains a support and at least a photosensitive layer disposed on the support, wherein the photosensitive layer contains a charge generating material and a compound expressed by the following Structural Formula (1), and wherein, in the Structural Formula (1), “R1” and “R2” may be identical to each other or different, and represent any one of hydrogen atom, alkyl group which may be substituted, cycloalkyl group which may be substituted and aralkyl group which may be substituted.
    Type: Application
    Filed: September 15, 2006
    Publication date: March 15, 2007
    Inventors: Eiji Kurimoto, Keisuke Shimoyama, Michio Kimura, Shinichi Kawamura, Takeshi Takada, Yasuyuki Yamashita, Naohiro Toda, Hideo Nakamori
  • Publication number: 20070042284
    Abstract: A toner for developing an electrostatic image having a good combination of hot offset resistance and low temperature fixability. The toner includes (1) a resin having at least one group that can react with a compound having an active hydrogen in an amount of 2 pieces per molecule of the resin, and a colorant. The toner satisfies the following relationship: 3?G=R?Rideal?20, where G represents a ratio of a weight of components other than the colorant and the resin that are insoluble in the organic solvent to total weight of the toner, R represents a weight ratio of components included in the toner that are insoluble in the organic solvent to the total weight of the toner, and Rideal represents an ideal weight ratio of the colorant and the resin, which is calculated from a formula of the toner.
    Type: Application
    Filed: October 27, 2006
    Publication date: February 22, 2007
    Inventors: Takeshi Takada, Chiaki Tanaka, Naohiro Watanabe
  • Publication number: 20070015074
    Abstract: An electrostatic latent image bearer, comprising a substrate; a photosensitive layer overlying the substrate; and a protective layer overlying the photosensitive layer, wherein the protective layer includes a binder resin comprising a polyol, a polyisocyanate and an organic silicon compound having a hydroxyl or a hydrolyzable group.
    Type: Application
    Filed: July 14, 2006
    Publication date: January 18, 2007
    Inventors: Akihiro Sugino, Takaai Ikegami, Takeshi Takada
  • Patent number: 7163775
    Abstract: A toner for developing an electrostatic image having a good combination of hot offset resistance and low temperature fixability. The toner includes (1) a resin having at least one group that can react with a compound having an active hydrogen in an amount of 2 pieces per molecule of the resin, and a colorant. The toner satisfies the following relationship: 3?G=R?Rideal?20, where G represents a ratio of a weight of components other than the colorant and the resin that are insoluble in the organic solvent to total weight of the toner, R represents a weight ratio of components included in the toner that are insoluble in the organic solvent to the total weight of the toner, and Rideal represents an ideal weight ratio of the colorant and the resin, which is calculated from a formula of the toner.
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: January 16, 2007
    Assignee: Ricoh Company Limited
    Inventors: Takeshi Takada, Chiaki Tanaka, Naohiro Watanabe
  • Publication number: 20060199092
    Abstract: An electrostatic latent image bearer, including a substrate and a photosensitive layer located overlying the substrate, wherein an outermost layer of the electrostatic latent image bearer includes a binder resin and an electroconductive particulate material, wherein the electroconductive particulate material has the following formula: MxSbyOz wherein M represents a metallic element; and x, y and z represent molar ratios for respective elements.
    Type: Application
    Filed: March 3, 2006
    Publication date: September 7, 2006
    Inventors: Akihiro Sugino, Takaaki Ikegami, Takeshi Takada