Patents by Inventor Robert E. Detiefsen

Robert E. Detiefsen 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).

  • Stabilized compositions containing liquid substituted 2H-benzotriazole mixtures
    Patent number: 5095062
    Abstract: Liquid substituted, 2H-benzotriazole mixtures are prepared by alkylation with concomitant dealkylation, fragmentation and realkylation of 2-(2-hydroxy-5-alkylphenyl)-2H-benzotriazoles or of 2-(2-hydroxy-3,5-dialkylphenyl)-2H-benzotriazoles with straight or branched alkenes of 8 to 30 carbon atoms in the presence of an acid catalyst at 100.degree.-200.degree. C. The liquid mixtures exhibit outstanding efficacy in protecting organic substrates from light induced deterioration as well as good resistance to loss by volatilization or exudation during the processing of stabilized compositions at elevated temperatures.
    Type: Grant
    Filed: September 5, 1990
    Date of Patent: March 10, 1992
    Assignee: Ciba-Geigy Corporation
    Inventors: Roland A. E. Winter, Robert E. Detiefsen, Werner Stegmann, Reto Luisoli, David Leppard