Patents by Inventor D. W. Calvin

D. W. Calvin 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).

  • Dentifrice compositions containing fumed silica with sorbed fluoride
    Patent number: 4172121
    Abstract: A dentifrice in a liquid vehicle containing fumed silica with fluoride sorbed thereon giving free fluoride ions in the composition for the therapeutic treatment of teeth.
    Type: Grant
    Filed: August 21, 1978
    Date of Patent: October 23, 1979
    Assignee: The Dow Chemical Company
    Inventors: D. W. Calvin, Marylu B. Gibbs