(C) Peter Meiers - http://www.fluoride-history.de
Tin Fluorides (for dentifrices)
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."
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
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)
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
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
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
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."
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."
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
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