Patents by Inventor Nigel Wyndham Drewe

Nigel Wyndham Drewe 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).

  • Formulation process
    Patent number: 4118218
    Abstract: A process of preparing a solid herbicidal formulation containing a high concentration of a bipyridylium diquaternary salt, which comprises injecting a solution of the bipyridylium salt into a heated fluid bed of a particulate carrier, so that the bipyridylium salt is deposited onto the carrier.
    Type: Grant
    Filed: June 14, 1976
    Date of Patent: October 3, 1978
    Assignee: Imperial Chemical Industries Limited
    Inventors: Nigel Wyndham Drewe, Peter Robin Hodson, Clive Gilroy Robson
  • Herbicidal compositions having improved stability
    Patent number: 4075002
    Abstract: Herbicidal compositions are provided which contain a solid herbicide dispersed in an aqueous solution of a herbicidal bipyridylium salt along with a cationic dispersing agent for added stability of the formulation.
    Type: Grant
    Filed: January 15, 1973
    Date of Patent: February 21, 1978
    Assignee: Imperial Chemical Industries Limited
    Inventors: Nigel Wyndham Drewe, Roger John Parker, Tharwat Fouad Tadros