Patents by Inventor Seiichiro Iida

Seiichiro Iida 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 of preparing water-absorbing resin
    Patent number: 5652309
    Abstract: A method of preparing a water-soluble resin, which comprises the steps of: subjecting an aqueous solution of a first water-soluble ethylenically unsaturated monomer to a first-stage water-in-oil type of reverse-phase suspension polymerization using a water-soluble radical polymerization initiator in a hydrophobic organic solvent in the presence of an emulsifier and optionally a crosslinking agent, thereby forming a slurry containing hydrous polymer gel particles; adding to said slurry a nonionic or anionic surface active agent having an HLB of at least 7 and higher than that of said emulsifier and an aqueous solution of a second water-soluble ethylenically unsaturated monomer so as to absorb the aqueous solution of the second monomer in said hydrous polymer gel particles; and carrying out a second-stage polymerization of said second monomer.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: July 29, 1997
    Assignee: Mitsubishi Chemical Corporation
    Inventors: Kiichi Itoh, Seiichiro Iida