(C) Peter Meiers - http://www.fluoride-history.de
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Tin Fluorides (for dentifrices) |
1947 Richard S. Manly is a former student of Harold C. Hodge, University of Rochester Richard S. MANLY, assignor to the Procter & Gamble Company: "Improvements in and relating to preparations for use in contact with the teeth"; British Patent GB 644,339; application made in U.S.A. March 12, 1947; filed March 11, 1948; pat. Oct. 11, 1950 "Examples of fluoride complexes coming within the scope of the invention are: potassium fluotitanate, ammonium fluozirconate, potassium fluohafniate, sodium fluostannate, lithium fluozirconate, and potassium fluogermanate."
1951 William F. BRUCE, assignor to Wyeth Incorporated, Philadelphia, Pa.: "Potassium stannous fluoride", US Patent 2,606,812; filed Aug. 31, 1951; pat. Aug. 12, 1952
1953 William H. NEBERGALL, assignor to Indiana University Foundation, Bloomington, Indiana: "Dentifrice preparations", US Patent 2,876,166; filed July 8, 1953; pat. Mar. 3, 1959 the (?) CREST patent (-> see also the Nebergall patents filed in 1955)
1955 William H. NEBERGALL, assignor to Indiana University Foundation, Bloomington, Ind.: "Stannous chlorofluoride, method of preparing same, and dentifrice compositions therewith", US Patent 2,836,544; filed Feb. 7, 1955; pat. May 27, 1958 - Richard E. HAGER, Carroll R. REISS, assignors to Procter & Gamble Company, Cincinnati, Ohio: "Dentifrice containing a stannous compound and a carboxylated alkyl cellulose ether", US Patent 2,839,448; filed Feb. 9, 1955; pat. June 17, 1958 Stannous fluoride as the fluoride ingredient - William H. NEBERGALL, assignor to Indiana University Foundation, Bloomington, Ind.: "Distannousmonochlorotrifluoride and dentifrice compositions therewith", US Patent 2,882,204; filed May 31, 1955; pat. Apr. 14, 1959
1956 Joe E. GILLILAND, Raymond RAY, and Wayne E. WHITE, assignors to Ozark-Mahoning Company, Tulsa, Oklahoma: "Method of production of stannous fluoride", US Patent 2,924,508; filed Sept. 20, 1956; pat. Feb. 9, 1960 commercially available substantially chemically pure tin powder is reacted with anhydrous or substantially anhydrous hydrogen fluoride
1957 Joe E. GILLILAND, Raymond RAY, and Wayne E. WHITE, assignors to Ozark-Mahoning Company, Tulsa, Oklahoma: "Method of production of stannous fluoride", US Patent 2,955,914; filed Aug. 26, 1957; pat. Oct. 11, 1960 hydrofluoric acid added to a mass of pure metallic tin
1960 Joe E. GILLILAND, Raymond RAY, and Wayne E. WHITE, assignors to Ozark-Mahoning Company, Tulsa, Oklahoma: "Hydrogen fluoride detinning process and production of stannous fluoride", US Patent 3,097,063; filed Feb. 8, 1960; pat. July 9, 1963 "... the basic raw material for the can manufacturing industry is sheet steel of usually 0.01 inch thickness with a coating of pure tin averaging less than 1 percent of the weight of the steel. This tin makes the scrap unsuitable for return to steel furnaces as well as providing a material of importance as a source of tin metal. ... Therefore, an object of the invention is to provide an extremely rapid process of removing the coating from plated metals which are themselves unreactive toward hydrogen fluoride [while the tin is dissolved as stannous fluoride] ... Stannous fluoride is presently of great commercial interest as an additive for dentifrices to supply fluorine values to human teeth for the purpose of reducing the incidence of dental caries."
1961 William E. COOLEY, Robert J. GRABENSTETTER, and Robert W. BROGE, assignors to the Procter & Gamble Company, Cincinnati,Ohio: "Abrasive for dentifrice composition", US Patent 3,151,027; filed June 7, 1961; pat. Sept. 29, 1964 "... object of this invention is to provide a preferred dentifrice in which a substantial amount of stannous and fluoride ions do not react with the cleaning agent and thus remain available for treatment of the tooth surfaces on use."
1963 Joseph C. MUHLER, assignor to Indiana University Foundation: "Oral compositions for caries prophylaxis containing stannous fluorozirconate", US Patent 3,266,996; filed June 27, 1963; pat. Aug. 16, 1966
1965 Wayne E. WHITE, Albert W. JACHE, assignors to Ozark-Mahoning Company, Tulsa, Oklahoma: "Stannous Hexafluorozirconate", US Patent 3,337,295; filed Feb. 8, 1965; pat. Aug. 22, 1967 preparation for use in caries prevention
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