Patents by Inventor Shinji Yatabe

Shinji Yatabe 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: 8658339
    Abstract: A negative charge controlling agent, wherein: the negative charge controlling agent comprises polycondensation product obtained by a polycondensation reaction of phenols and aldehydes; and the phenols comprises a (A) mononucleus phenolic compound which has one phenolic hydroxy group in which a hydrogen is bonded at the ortho position of a hydroxyl group of the phenolic hydroxy group and a (B) multinucleus phenolic compound which has at least two phenolic hydroxy groups in which a hydrogen is bonded at the ortho position of a hydroxyl group of each of the phenolic hydroxy group; and the content of the (B) phenolic compound in the phenols is 1 to 30 mol %.
    Type: Grant
    Filed: January 21, 2004
    Date of Patent: February 25, 2014
    Assignee: Fujikura Kasei Co., Ltd.
    Inventors: Takayuki Ishimoto, Yutaka Kukimoto, Shinji Yatabe
  • Publication number: 20090035680
    Abstract: Provided are a positive charge controlling agent which is excellent in compatibility with and dispersibility in a binder resin, prevented from discoloring, excellent in chargeability, and reduced in the content of organic compounds having low boiling points, thereby giving no strong odor; a process for producing the same; and an electrophotographic toner which exhibits excellent chargeability and colorability, and the controlled production of VOC. The positive charge controlling agent includes a copolymer obtained by copolymerizing a styrene monomer (M1), a (meth)acrylic acid alkyl ester monomer (M2), and a quaternary ammonium salt (M3) of a dialkylaminoalkyl(meth)acrylate monomer, wherein a copolymerizing ratio (mass %) of the monomers, (M1)+(M2):(M3), is 99.5:0.5 to 65:35, and at least one end thereof is RCOO— or RO—, where R is an alkyl group, an aryl group, an aralkyl group, or an alicyclic group.
    Type: Application
    Filed: April 23, 2007
    Publication date: February 5, 2009
    Applicant: FUJIKURA KASEI CO., LTD.
    Inventors: Takayuki Ishimoto, Shinji Yatabe
  • Publication number: 20060083999
    Abstract: A negative charge controlling agent, wherein: the negative charge controlling agent comprises polycondensation product obtained by a polycondensation reaction of phenols and aldehydes; and the phenols comprises a (A) mononucleus phenolic compound which has one phenolic hydroxy group in which a hydrogen is bonded at the ortho position of a hydroxyl group of the phenolic hydroxy group and a (B) multinucleus phenolic compound which has at least two phenolic hydroxy groups in which a hydrogen is bonded at the ortho position of a hydroxyl group of each of the phenolic hydroxy group; and the content of the (B) phenolic compound in the phenols is 1 to 30 mol %.
    Type: Application
    Filed: January 21, 2004
    Publication date: April 20, 2006
    Inventors: Takayuki Ishimoto, Yutaka Kukimoto, Shinji Yatabe