Patents Assigned to Hercules Powder Company Limited
  • Suspension medium
    Patent number: 4155314
    Abstract: Stable suspensions of solid particles are formed by dispersing the particles in a pseudoplastic aqueous medium containing in solution xanthan gum and at least one non-ionic water-soluble polymer, exemplified by guar gum, in proportions providing an unexpectedy high ratio of yield point to plastic viscosity. The medium is especially useful in the planting of seeds which may be pre-germinated.
    Type: Grant
    Filed: March 20, 1978
    Date of Patent: May 22, 1979
    Assignee: Hercules Powder Company Limited
    Inventors: William P. O'Callaghan, Gianfranco Mecatti
  • Sizing method and composition for use therein
    Patent number: 3957574
    Abstract: In the production of sized paper and board using ketene dimer as sizing agent, there is used concomitantly with the ketene dimer a cationic polyelectrolyte so as to increase the sizing effect of the ketene dimer. The cationic polyelectrolyte is normally a dye fixative selected from water-soluble dicyandiamide-formaldehyde condensates. The cationic polyelectrolyte may be mixed with the ketene dimer so as to form a novel sizing composition which is preferably used in the form of an emulsion.
    Type: Grant
    Filed: January 6, 1975
    Date of Patent: May 18, 1976
    Assignee: Hercules Powder Company Limited
    Inventor: Thomas Edward Anderson