Patents by Inventor Stuart W. Longworth

Stuart W. Longworth 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).

  • Inhibition of deposition in aqueous systems
    Patent number: 5122278
    Abstract: A method for treating an aqueous system is disclosed which comprises incorporating therein a water soluble organic sulphonate copolymer and an optionally N-substituted water soluble copolymer of acrylamide or methacrylamide and a copolymerizable monomer.
    Type: Grant
    Filed: July 26, 1990
    Date of Patent: June 16, 1992
    Assignee: W. R. Grace & Co.-Conn.
    Inventors: Stuart W. Longworth, Brian Greaves, John J. Bennison
  • Prevention of corrosion
    Patent number: 4689201
    Abstract: Corrosion in liquid, especially aqueous systems such as cooling systems, is controlled by the addition of a vegetable tannin or a derivative thereof, a triazole, a hydroxylamine, a neutralizing amine, and a water soluble salt of a Group II metal, in particular zinc, magnesium or calcium.
    Type: Grant
    Filed: March 5, 1985
    Date of Patent: August 25, 1987
    Assignee: Dearborn Chemicals Limited
    Inventors: Stuart W. Longworth, John G. Baker
  • Treatment of aqueous systems
    Patent number: 4566972
    Abstract: A method of inhibiting and preventing scale in an aqueous system is described which comprises incorporating in the water at least one amino carboxylate having the formula:RN[--(CH.sub.2).sub.x --Z].sub.2in which x is 1 or 2, R represents --(CH.sub.2).sub.x --Z or --CH.sub.2 CH.sub.2 N[--(CH.sub.2).sub.x --Z].sub.2 and Z represents a --COOH group, or a salt thereof, and at least one water-soluble copolymer possessing recurring units of the formula: ##STR1## wherein R.sub.1 represents hydrogen, lower alkyl or --CH.sub.2 COOH, R.sub.2 represents hydrogen or lower alkyl, X represents --COOH and Z represents hydrogen or --COOH, or X and Z together represent --CO--O--CO--, and Y represents --SO.sub.3 H, --C.sub.6 H.sub.5 SO.sub.3 H (para) or --CONHQ(R.sub.3)(R.sub.4) SO.sub.3 H in which Q represents --CH.sub.2 -- or --CH.sub.2 --CH.sub.2 -- and R.sub.3 and R.sub.4 independently represent hydrogen, phenyl, substituted phenyl, C 1-12 linear or branched alkyl or C 3-12 cycloalkyl, or a salt thereof.
    Type: Grant
    Filed: January 15, 1985
    Date of Patent: January 28, 1986
    Assignee: Dearborn Chemicals, Ltd.
    Inventors: John J. Bennison, Stuart W. Longworth, John G. Baker