Patents by Inventor Akihiro Kotsugai

Akihiro Kotsugai 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: 20220110934
    Abstract: A pharmaceutical composition including particles each containing a water-soluble base material and a poorly water-soluble compound, the water-soluble base material containing a rapidly water-soluble compound, wherein the poorly water-soluble compound is a kinase inhibitor and exists in an amorphous state in the water-soluble base material.
    Type: Application
    Filed: December 22, 2021
    Publication date: April 14, 2022
    Applicants: Ricoh Company, Ltd., Shinshu University
    Inventors: Takashi SATO, Takeshi Shimosato, Tatsuru Moritani, Tadahiko Morinaga, Yuichi Sato, Akihiro Kotsugai
  • Publication number: 20190264322
    Abstract: Provided are conductive diamond particles including: particulate bases; and boron-doped diamond films on at least part of surfaces of the particulate bases, wherein an average particle diameter of the conductive diamond particles is greater than 0.5 micrometers, and wherein in Raman spectrum measurement of the conductive diamond particles at an excitation wavelength of 532 micrometers, a ratio of an intensity of the conductive diamond particles at 1,580 cm?1 to an intensity of the conductive diamond particles at 1,332 cm?1 is less than 0.090.
    Type: Application
    Filed: October 26, 2017
    Publication date: August 29, 2019
    Inventors: Takeshi KONDO, Keito NAKAJIMA, Tatsuo AIKAWA, Makoto YUASA, Takahiro OSASA, Akihiro KOTSUGAI
  • Patent number: 8771914
    Abstract: The present invention provides a toner which, despite its spherical shape, makes it possible to prevent an external additive from being embedded in the toner easily or by a load generating low stress, reduce variation in image density, maintain cleaning ability and transfer ability throughout its long-term use and obtain excellent image quality, and further, provides a two-component developer, an image forming method and an image forming apparatus with the use of the toner. There is a toner including: base particles including a colorant and a resin, and hard fine particles, wherein the base particles and the hard fine particles are mixed together, and protruding portions formed of fine organic resin particles which are different in composition from a resin contained as a main component in the base particles are provided on surfaces of the base particles.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: July 8, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Akihiro Kotsugai, Hiroshi Yamashita
  • Patent number: 8741520
    Abstract: The present invention provides an image forming toner including at least a linear polyester resin (b1) as a binder resin, wherein the linear polyester resin (b1) is obtained by reacting a polyester diol (b11) having a polyhydroxycarboxylic acid skeleton, with a polyester diol (b12) other than the polyester diol (b11) in the presence of a chain extending agent.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: June 3, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Toyoshi Sawada, Akihiro Kotsugai, Akiyoshi Sabu
  • Patent number: 8691486
    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: Grant
    Filed: June 28, 2010
    Date of Patent: April 8, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Inoue, Akihiro Kotsugai, Akiyoshi Sabu, Shingo Sakashita, Yukiko Nakajima, Keiko Osaka
  • Patent number: 8679714
    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: Grant
    Filed: September 9, 2010
    Date of Patent: March 25, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Inoue, Akihiro Kotsugai, Yoshihiro Moriya, Akiyoshi Sabu, Shingo Sakashita, Keiko Osaka, Yukiko Nakajima, Yoshitaka Yamauchi, Daiki Yamashita
  • Patent number: 8632932
    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: Grant
    Filed: December 30, 2009
    Date of Patent: January 21, 2014
    Assignee: Ricoh Company, Limited
    Inventors: Akiyoshi Sabu, Akihiro Kotsugai, Ryota Inoue, Keiko Osaka, Shingo Sakashita, Yukiko Nakajima, Satoshi Mochizuki
  • Patent number: 8623580
    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: Grant
    Filed: August 3, 2010
    Date of Patent: January 7, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Yukiko Nakajima, Akihiro Kotsugai, Ryota Inoue, Akiyoshi Sabu, Shingo Sakashita, Keiko Osaka
  • Patent number: 8603713
    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: Grant
    Filed: February 26, 2010
    Date of Patent: December 10, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Akihiro Kotsugai, Toyoshi Sawada, Ryota Inoue, Akiyoshi Sabu, Shingo Sakashita, Keiko Osaka, Yukiko Nakajima
  • Patent number: 8383307
    Abstract: The toner includes a binder resin; a release agent; a colorant; and a dispersing resin configured to disperse the release agent. The dispersing resin includes a polyhydroxycarboxylic acid unit obtained from an optically active monomer. The polyhydroxycarboxylic acid unit has an optical purity of not greater than 80%, wherein the optical purity is defined as the absolute value of difference between the mole percentage of a L-monomer in the optically active monomer and the mole percentage of a D-monomer in the optically active monomer.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: February 26, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Ryota Inoue, Akihiro Kotsugai, Toyoshi Sawada, Akiyoshi Sabu
  • Patent number: 8329374
    Abstract: There is provided a method for producing a carrier, which includes depositing a resin coating layer on the surface of a magnetic material; adding a treatment agent for a conductor precursor to the resin coating layer so as to treat the resin coating layer with the treatment agent; and exposing the treatment agent-added resin coating layer to a conductor precursor in a supercritical or subcritical fluid so as to form a conductor in the resin coating layer.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: December 11, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryota Inoue, Akihiro Kotsugai, Yoshihiro Moriya, Shingo Sakashita
  • Patent number: 8329370
    Abstract: An image forming apparatus including: a latent electrostatic image bearing member, a charging unit, an exposing unit, a developing unit, a transfer unit, and a fixing unit, wherein the toner contains at least a binder resin and a colorant, the binder resin contains a polyester resin obtained by polycondensation of an alcohol component with a carboxylic acid component containing a rosin compound, the amount of the rosin compound contained in the carboxylic acid component is 5% by mass or more based on the total mass of the alcohol component and carboxylic acid component, and the amount of an abietic acid contained in the toner is 1% by mass or less.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: December 11, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinya Nakayama, Akihiro Kotsugai, Akiyoshi Sabu
  • Patent number: 8263302
    Abstract: A carrier for electrophotographic developer, including a core material; and a layer comprising a binder resin, located overlying the core material, wherein the binder resin includes a segment including one or more polymerizable vinyl monomers as a structural unit; and another segment including a partial cleavage structure of polyhedral oligomeric silsesquioxane and/or another partial cleavage structure of polyhedral oligomeric silsesquioxane as a structural unit.
    Type: Grant
    Filed: September 8, 2009
    Date of Patent: September 11, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshihiro Moriya, Akihiro Kotsugai, Toyoshi Sawada, Ryota Inoue, Akiyoshi Sabu, Shingo Sakashita
  • Patent number: 8114560
    Abstract: The present invention provides a toner containing at least a binder resin, a releasing agent, and a colorant, wherein the binder resin contains at least a polyester resin (A) having a softening point Tm (A) of 120° C. to 160° C., a polyester resin (B) having a softening point Tm (B) of 80° C. or more and less than 120° C. and a composite resin (C) containing a condensation polymerization monomer and an addition polymerization monomer, at least any one of the polyester resins (A) and (B) is a polyester resin prepared by condensation-polymerizing an alcohol component substantially composed of only aliphatic alcohol with a carboxylic acid component, and 65% or more of the alcohol component is 1,2-propanediol.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: February 14, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinya Nakayama, Akihiro Kotsugai, Akiyoshi Sabu, Hiroshi Yamashita, Hiroshi Yamada, Junichi Awamura, Tsuyoshi Sugimoto
  • Patent number: 8017292
    Abstract: To provide a toner produced by emulsifying or dispersing in an aqueous medium particles containing at least polyester resin particles and by aggregating the polyester resin particles, wherein the polyester resin particles contain a polyester resin, the polyester resin is produced by condensation polymerization of an alcohol component containing 65 mol % or more 1,2-propanediol in a dihydroxy alcohol component and a carboxylic acid component containing purified rosin, and the softening point of the polyester resin is 80° C. or more and less than 120° C., and wherein the toner comprises a colorant and a releasing agent.
    Type: Grant
    Filed: April 30, 2008
    Date of Patent: September 13, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Akiyoshi Sabu, Akihiro Kotsugai, Shinya Nakayama, Hiroshi Yamashita, Tsuyoshi Sugimoto, Hiroshi Yamada, Junichi Awamura
  • Patent number: 8007974
    Abstract: A toner that is excellent in low-temperature fixing property, offset resistance, storage stability, charge rising property, charge stability with time and pulverizability and allows for forming high-quality images over a long period of time. The toner contains at least a binder resin, a colorant and a charge controlling agent, wherein the charge controlling agent contains an aromatic oxycarboxylic acid metal compound having a trivalent or more central metal, the binder resin comprises a polyester resin (A) having a softening point Tm (A) of 120° C. to 160° C. and a polyester resin (B) having a softening point Tm (B) of 80° C. to less than 120° C., and at least any one of the polyester resins (A) and (B) contains 1,2-propane diol at 65 mol % or more in a divalent alcohol component and can be obtained by condensation polymerizing an alcohol component substantially composed of only an aliphatic alcohol with a carboxylic acid component.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: August 30, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinya Nakayama, Akihiro Kotsugai, Yasuaki Iwamoto, Yasutada Shitara
  • Patent number: 7960083
    Abstract: An image forming apparatus including a charging unit, an exposing unit, a developing unit, a transferring unit, and a fixing unit. A toner containing a colorant and a binder resin which contains a polyester resin (A) and a polyester resin (B) having a softening point 10° C. or more higher than that of the polyester resin (A); the polyester resin (A) is a (meth)acrylic acid-modified rosin derived resin having a polyester unit obtained by polycondensation of an alcohol component, which contains 65 mol % or more of 1,2-propanediol in a dihydric alcohol component, and a carboxylic acid component containing a (meth)acrylic acid-modified rosin; the polyester resin (B) is a purified rosin derived resin having a polyester unit obtained by polycondenstation of an alcohol component, which contains a total of 70 mol % or more of 1,2-propanediol and 1,3-propanediol in a dihydric alcohol component, and a carboxylic acid component containing purified rosin.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: June 14, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinya Nakayama, Akihiro Kotsugai, Akiyoshi Sabu
  • Publication number: 20110129775
    Abstract: The present invention provides an image forming toner including at least a linear polyester resin (b1) as a binder resin, wherein the linear polyester resin (b1) is obtained by reacting a polyester diol (b11) having a polyhydroxycarboxylic acid skeleton, with a polyester diol (b12) other than the polyester diol (b11) in the presence of a chain extending agent.
    Type: Application
    Filed: June 17, 2009
    Publication date: June 2, 2011
    Inventors: Toyoshi Sawada, Akihiro Kotsugai, Akiyoshi Sabu
  • 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