Patents Examined by Allan Liebermann
  • Process for the production of expandable ethylenically unsaturated polymer particles
    Patent number: 4080344
    Abstract: Expandable ethylenically unsaturated polymer particles are produced by using in the process a suspension stabilizer comprising calcium carbonate particles having the surfaces thereof treated with resin acid. The method for the production of such expandable ethylenically unsaturated polymer particles from ethylenically unsaturated polymer particles includes suspending such particles in water and impregnating the particles with an organic expanding agent having a boiling point lower than the softening point of the polymer particles.
    Type: Grant
    Filed: March 4, 1975
    Date of Patent: March 21, 1978
    Assignee: Sekisui Kaseihin Kogyo Kabushiki Kaisha
    Inventors: Toshiki Ikeda, Fumito Yamai, Tomohiko Ishida