Patents by Inventor Rudolf Hirschberg

Rudolf Hirschberg 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).

  • Chlorofluoroferrate(II,III), a process for its manufacture, its use and a grinding wheel containing chlorofluoroferrate(II,III)
    Patent number: 4370148
    Abstract: Chlorofluoroferrates(II,III) are manufactured by fusing alkali metal halides or ammonium halides with an iron(III) halide and metallic iron. The starting materials used are, in particular, (a) an alkali metal chloride or ammonium chloride, (b) an alkali metal fluoride or ammonium fluoride, (c) anhydrous iron(III) chloride and (d) iron powder. The reaction is carried out a temperature of 300.degree. to 900.degree. C. The chlorofluoroferrates, which have a markedly lower hygroscopicity compared with customary chloroferrates, are particularly suitable for use as active fillers for grinding wheels.
    Type: Grant
    Filed: July 9, 1981
    Date of Patent: January 25, 1983
    Assignee: Riedel-De Haen Aktiengesellschaft
    Inventors: Rudolf Hirschberg, Bernd Schonfeld
  • Non-toxic, active filler for grinding disks, its use and grinding disk containing same
    Patent number: 4263016
    Abstract: In grinding disks, toxic lead chloride and antimony sulfide may be replaced by non-toxic alkali metal chloroferrates (II,III) produced by melting together alkali metal chloride, anhydrous ferric chloride and iron powder.
    Type: Grant
    Filed: August 13, 1979
    Date of Patent: April 21, 1981
    Assignee: Riedel-de Haen Aktiengesellschaft
    Inventors: Rudolf Hirschberg, Bernd Schonfeld