Patents by Inventor Derek Francis Croxall

Derek Francis Croxall 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).

  • Crystals and their manufacture
    Patent number: 4019950
    Abstract: In a hydrothermal process for manufacturing crystals of metal carbonates, including single crystals of lead carbonate of the cerussite crystalline form, the nutrient material consists of a carbonate or basic carbonate of the said metal, the solvent medium consists of a 0.5 to 5.0 molar aqueous solution of an alkali metal bicarbonate, and the heating is carried out in an autoclave under controlled temperature conditions such that the exterior of the autoclave wall adjacent to the nutrient and the solvent medium in the vicinity thereof is maintained at 200.degree. C to 400.degree. C, and that the exterior of the autoclave wall adjacent to the region of the solvent medium remote from the nutrient is maintained at 170.degree. C to 315.degree. C and at a temperature from 5.degree. C to 150.degree.
    Type: Grant
    Filed: November 7, 1975
    Date of Patent: April 26, 1977
    Assignee: The General Electric Company Limited
    Inventors: Derek Francis Croxall, Robert Christopher Kell, Robert Lambert