Patents by Inventor Siegfried Schiebler

Siegfried Schiebler 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).

  • Patent number: 5342723
    Abstract: Use of biscationic acid imide and acid imide derivatives whose anion is the stoichiometric equivalent of one or more organic or inorganic, mixed or non-mixed anions, the compounds also being able to exist as mixed crystals with different cations, individually or in combination, as charge controllers for toners and developers employed for electrophotographic copying or multicopying of originals and for printing electronically, optically or magnetically stored data or in color proofing, and as charge controllers for powders and powder paints.
    Type: Grant
    Filed: June 25, 1992
    Date of Patent: August 30, 1994
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Hans-Tobias Macholdt, Siegfried Schiebler, Jorg Gitzel, Erwin Dietz
  • Patent number: 5254796
    Abstract: The invention relates to an ecologically favorable process for the hydrolytic decomposition of halogen-containing compounds of the formula CX.sub.4 or CHX.sub.3 or mixtures of these compounds, in which X as halogen is chlorine or bromine or a combination thereof, in an aqueous-alkaline medium, which comprises first keeping the aqueous-alkaline reaction mixture comprising the abovementioned halogen-containing compounds at a temperature of between 0.degree. and 1000.degree. C. under the autogenous pressure which is formed in a closed reaction vessel for a period of up to 10 hours and then subjecting the mixture to a heat treatment at a temperature of between 70.degree. and 150.degree. C. under the autogenous pressure which is formed therein, in the presence of sulfite. The process according to the invention is particularly suitable for hydrolytic decomposition of halogen-containing reaction products from aqueous-alkaline hypohalite oxidations.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: October 19, 1993
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Erwin Dietz, Siegfried Schiebler
  • Patent number: 3984433
    Abstract: A process for preparing very pure copper phthalocyanine pigments of the .alpha.-modification, wherein substituted or unsubstituted copper phthalocyanines having different degrees of purity are converted into copper phthalocyanine salts capable of being isolated, with the aid of suitable acids which dissolve the impurities contained in the dyestuff, wherein these salts are separated from the acid, the copper phthalocyanines of the .alpha.-modification are set free in a pure form from the copper phthalocyanine salts by the action of water and wherein the isolated copper phthalocyanine is subject in an aqueous suspension to a mechanical fine division. This process yields copper phthalocyanines of the .alpha.-modification in a very pure form without causing problems with respect to the waste water.
    Type: Grant
    Filed: December 21, 1973
    Date of Patent: October 5, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Ernst Spietschka, Siegfried Schiebler, Wolfgang Tronich