Patents by Inventor Koichi Horiguchi

Koichi Horiguchi 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).

  • Method for purifying a polyphenylene ether with amino carboxylic acid derivative
    Patent number: 5214128
    Abstract: A novel method for purifying a polyphenylene ether is disclosed. The method is characterized in that in separating a polyphenylene ether from a reaction product obtained by oxidative polymerization of a 2,6-di-substituted-phenol by means of a precipitation polymerization method in which a polymer is precipitated in the presence of a catalyst comprising a combination of a copper ion, a halide ion and not less than one type of amines and purifying a polyphenylene ether, wherein an amino carboxylic acid derivative is added to the reaction product and then a polymer is washed with a poor solvent for the polyphenylene ether.
    Type: Grant
    Filed: November 12, 1991
    Date of Patent: May 25, 1993
    Inventors: Koichi Horiguchi, Sadao Ibe, Katsuo Tsuguma