Patents by Inventor Yasumasa Suda

Yasumasa Suda 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: 6103896
    Abstract: A process for the production of a metal phthalocyanine excellent in color-related properties such as tinting strength, clearness and hue, in which no reactions of raw materials with a solvent take place and a substance harmful to human bodies such as polychlorinated biphenyl (PCB) is not formed, the process comprising heating phthalic anhydride or phthalimide, urea, metal salt and a catalyst in mixed solvents of chlorinated benzene and a linear hydrocarbon.
    Type: Grant
    Filed: April 2, 1999
    Date of Patent: August 15, 2000
    Assignee: Toyo Ink Manufacturing Co., Ltd.
    Inventors: Atsushi Endo, Yasumasa Suda
  • Patent number: 5910585
    Abstract: A process for the production of copper phthalocyanine, which overcomes the defect of a method using two reaction steps that since phthalimide formed in the first step adheres to the wall of a reactor and a stirring blade, the reaction in the second step does not smoothly proceed, so that the yield and the purity of the resultant pigment are low, and which process enables the industrially stable production of highly pure copper phthalocyanine at high yields,the process comprising the steps of(A) reacting phthalic anhydride or a phthalic anhydride derivative with ammonia to form phthalimide,(B) adding part or all of urea to the phthalimide obtained in step (A) and melting the mixture under heat to form a homogeneous slurry, and(C) adding copper or a copper compound and remaining urea if any to the slurry obtained in step (B) and forming a copper phthalocyanine or a copper phthalocyanine derivative in the presence of a catalyst.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: June 8, 1999
    Assignee: Toyo Ink Manufacturing Co., Ltd.
    Inventors: Atsushi Endo, Yasumasa Suda
  • Patent number: 5698740
    Abstract: A hole-transport material having excellent hole-transport capability and durability, suitable for use in an organic EL device and as an organic photoconductive material, has the formula (1).
    Type: Grant
    Filed: February 12, 1997
    Date of Patent: December 16, 1997
    Assignee: Toyo Ink Manufacturing Co., Ltd.
    Inventors: Toshio Enokida, Tadashi Ogawa, Yasumasa Suda