Patents by Inventor Edward J. Duff

Edward J. Duff 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).

  • Process for preparing fluorapatite
    Patent number: 4157378
    Abstract: The process of preparing analytically pure fluorapatite comprising reacting dicalcium phosphate dihydrate with hydrogen fluoride in aqueous solution, at a pH of from about 5 to about 8, at from about room temperature for about 7 days to about 100.degree. C. for about 2 days, the amount of fluoride ion being from about stoichiometric to about 1.1 times the stoichiometric amount of dicalcium phosphate dihydrate whereby solid analytically pure fluorapatite is formed.
    Type: Grant
    Filed: June 2, 1977
    Date of Patent: June 5, 1979
    Assignee: Colgate Palmolive Company
    Inventors: Kenneth Tomlinson, Edward J. Duff
  • Process for preparing dicalcium phosphate dihydrate having a portion of the calcium displaced by divalent metal ion
    Patent number: 4139599
    Abstract: Process for preparing dicalcium phosphate dihydrate with displacement 0.1 - 5% of the calcium by divalent metal ion.
    Type: Grant
    Filed: June 2, 1977
    Date of Patent: February 13, 1979
    Assignee: Colgate Palmolive Company
    Inventors: Kenneth Tomlinson, Edward J. Duff
  • Amine monofluorophosphates in dentifrices
    Patent number: 4105759
    Abstract: Novel bis long chain (C.sub.8 - C.sub.18) amine monofluorophosphates, particularly useful as substantive, slow release fluoride agents for anti-caries prophylaxis; the process of preparing said amine monofluorophosphates; and compositions containing an effective amount of said fluoride agent admixed with a pharmaceutical carrier, more particularly an oral composition.
    Type: Grant
    Filed: March 28, 1977
    Date of Patent: August 8, 1978
    Assignee: Colgate-Palmolive Company
    Inventors: Ronald S. Schreiber, Edward J. Duff