Patents by Inventor Yoshiyuki Sumiyama

Yoshiyuki Sumiyama 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).

  • Pervaporation method of selectively separating water from an organic material aqueous solution through aromatic imide polymer asymmetric membrane
    Patent number: 4997462
    Abstract: A pervaporation separation method of water from an organic material aqueous solution at a high separating efficiency is effected by using a specific asymmetric separating membrane comprising a heat-resistant, solvent-soluble aromatic imide polymer prepared by the polymerization and imidization of an aromatic tetracarboxylic acid component comprising, as a principal ingredient, at least one biphenyl tetracarboxylic acid compound with an aromatic diamine component comprising a principal member selected from: ##STR1## and an additional member selected from another aromatic diamine compounds having 2 to 5 benzene ring structures and different from the diamine compounds (I) and (II).
    Type: Grant
    Filed: April 5, 1990
    Date of Patent: March 5, 1991
    Assignee: Ube Industries, Ltd.
    Inventors: Masayuki Nakatani, Yoshiyuki Sumiyama, Yoshihiro Kusuki