Patents by Inventor Erich Gubler

Erich Gubler 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).

  • Process for the preparation of a hydroxyphenylcarboxylate
    Patent number: 4618700
    Abstract: Pentaerythrityl tetrakis-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] is prepared by transesterifying a lower alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate with pentaerythritol in the presence of a basic catalyst, without addition of an inert solvent and in a 15 to 50% excess of lower alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate over the stoichiometric amount of 4 moles per 1 mole of pentaerythritol.An extremely good yield of pure crystalline product is obtained by the process of the invention.
    Type: Grant
    Filed: December 12, 1984
    Date of Patent: October 21, 1986
    Assignee: Ciba-Geigy Corporation
    Inventors: Erich Gubler, Max Siegrist