Patents by Inventor Keitarou Seto

Keitarou Seto 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).

  • Polyimide precursor solution process for the production thereof coating or film obtained therefrom and process for producing the film
    Patent number: 5854380
    Abstract: This invention provides a polyimide precursor solution having high concentration and low viscosity and a production process thereof, and polyimide coatings and films having excellent physical properties obtained therefrom and a production process thereof. Particularly, it relates to a polyimide precursor solution which contains a salt of a specific diamine with a specific tetracarboxylic acid, as its solute; to a process for the production of the polyimide precursor solution, which comprises allowing 1 mole of a specified diamine to react with 0.3 to 0.9 mole of a specific tetracarboxylic acid dianhydride, thereby obtaining a diamine, and subsequently adding 0.95 to 1.
    Type: Grant
    Filed: June 5, 1997
    Date of Patent: December 29, 1998
    Assignee: Unitika Ltd.
    Inventors: Keitarou Seto, Yoshiaki Echigo, Shoji Okamoto, Minoru Saitou