Patents by Inventor Frederick Campbell

Frederick Campbell 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).

  • Surfactant and dispersible or emulsifiable compositions employing surfactant
    Patent number: 5536445
    Abstract: A surfactant comprising a carboxylic acid ester or amide carrying a terminal strong acid group selected from carboxymethyl, sulphate, sulphonate, phosphate and phosphonate, suitable for stabilising dispersions of solids in organic liquids and oil/water emulsions, processes for the preparation of the surfactant and dispersions and emulsions containing the surfactant. A preferred species of the surfactant is a poly(hydroxyalkanecarboxylic acid) having the strong acid group attached, either directly or through a linking group, to a terminal hydroxy or carboxylic acid group.
    Type: Grant
    Filed: December 14, 1993
    Date of Patent: July 16, 1996
    Assignee: Zeneca Limted
    Inventors: Frederick Campbell, John D. Schofield, Alan S. Baker
  • Surfactant products of poly(hydroxyalkanecarboxylic acid) phosphate esters
    Patent number: 5300255
    Abstract: A surfactant comprising a carboxylic acid ester or amide carrying a terminal strong acid group selected from carboxymethyl, sulphate, sulphonate, phosphate and phosphonate, suitable for stabilising dispersions of solids in organic liquids and oil/water emulsions, processes for the preparation of the surfactant and dispersions and emulsions containing the surfactant. A preferred species of the surfactant is a poly(hydroxyalkanecarboxylic acid) having the strong acid group attached, either directly or through a linking group, to a terminal hydroxy or carboxylic acid group.
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: April 5, 1994
    Assignee: Imperial Chemical Industries, PLC.
    Inventors: Frederick Campbell, John D. Schofield, Alan S. Baker
  • Composition
    Patent number: 4861380
    Abstract: A composition comprising a finely-divided non-magnetic solid and a dispersant comprising a poly(C.sub.2-4 -alkyleneimine) carrying at least two mono- or poly-(carbonyl-C.sub.1-7 -alkyleneoxy) groups, a dispersion of the composition in an organic medium and a dispersant comprising a poly(C.sub.2-4 -alkyleneimine) carrying at least two carbonyl- C.sub.1-7 -alkyleneoxy groups.
    Type: Grant
    Filed: October 27, 1988
    Date of Patent: August 29, 1989
    Assignee: Imperial Chemical Industries PLC
    Inventors: Frederick Campbell, John M. Geary, John D. Schofield
  • Dispersion
    Patent number: 4645611
    Abstract: A dispersion of finely divided particles of a magnetic material in an organic liquid containing a dispersant comprising an amine carrying a poly(carbonylalkyleneoxy) chain (PCAO chain) in which the alkylene groups contain up to 8 carbon atoms, or an acid-salt thereof. The dispersion is useful for the preparation of magnetic recording media such as video, audio and computer recording tapes and discs. Certain of the dispersants are novel, especially a polyethyleneimine carrying at least two PCAO chains.
    Type: Grant
    Filed: February 1, 1985
    Date of Patent: February 24, 1987
    Assignee: Imperial Chemical Industries Plc
    Inventors: Frederick Campbell, Peter K. Davies, John D. Schofield