Patents by Inventor Thomas St{umlaut over (a)}hrfeldt

Thomas St{umlaut over (a)}hrfeldt 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).

  • Synergistic stabilizer mixture based on polyalkyl-1-oxa-diazaspirodecane compounds
    Patent number: 6174940
    Abstract: The present invention relates to mixtures comprising the compound I in a proportion of 65-95% by weight, the compound II in a proportion of 5-35% by weight and the compound III in a proportion of 0-10% by weight wherein the substituents are as defined in the description, and to mixtures with other compounds. The mixtures are suitable for stabilizing organic material against the effect of light and heat.
    Type: Grant
    Filed: August 13, 1998
    Date of Patent: January 16, 2001
    Assignee: Clariant GmbH
    Inventors: Thomas St{umlaut over (a)}hrfeldt, Mathias Mehrer, Matthias Z{umlaut over (a)}h, Gerhard Pfahler
  • Light stabilizers based on sterically hindered amines
    Patent number: 6172232
    Abstract: The present invention relates to novel compounds of the formula (I) in which the substituents have the meaning defined in the description. These novel compounds are excellent stabilizers for organic material against the damaging effects of light, heat and oxygen.
    Type: Grant
    Filed: September 3, 1998
    Date of Patent: January 9, 2001
    Assignee: Clariant GmbH
    Inventor: Thomas St{umlaut over (a)}hrfeldt