Patents by Inventor Keisho Nakanishi

Keisho Nakanishi 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).

  • Calcium carbonate scale inhibitor having organophosphonate, water soluble acrylic or maleic copolymer and citric acid
    Patent number: 5259985
    Abstract: A scale inhibitor for a calcium-type scale, which includes ingredients of:(a) an organophosphonic acid or its salt having an scale inhibiting activity;(b) a water-soluble acrylic acid-type or maleic acid-type polymer constituted by at least two kinds of monomer unit composed of a vinyl monomer having a carboxyl group or another polar group; and(c) citric acid or its salt.
    Type: Grant
    Filed: August 26, 1991
    Date of Patent: November 9, 1993
    Assignee: Katayama Chemical, Incorporated
    Inventors: Keisho Nakanishi, Masatsune Okuma, Sakae Katayama, deceased