Patents by Inventor Brigitta Otto

Brigitta Otto 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: 6417320
    Abstract: The production of linear polyester by the interchange of ester radicals or esterification and polycondensation of multivalent alcohols with multivalent carboxylic acids takes place by means of catalysts. In order that the catalyst features the lowest possible content of catalytically active metal compound, the carrier substance that forms the heterogeneous phase comprises particles of the finest grain and of porous structure and features a surface of great inner, reactive and/or coordinated centers, whereby a catalytically active metal compound is adsorbed in the pores.
    Type: Grant
    Filed: February 25, 2000
    Date of Patent: July 9, 2002
    Assignee: Zimmer Aktiengesellschaft
    Inventors: Brigitta Otto, Karl Ulrich Thiele, Xiaogang Guo
  • Patent number: 6358578
    Abstract: The present invention comprises a method of producing polyester transesterification of at least a dicarboxylic acid dialkyl ester or esterification of at least a dicarboxylic acid with at least a diol and subsequent precondensation and polycondensation in the presence of the usual catalysts, whereby the polycondensation and optionally the esterification take place in the presence of an additional carbon containing co-catalyst, preferably activated charcoal with a specific surface area of more than 500 m2/g and an average grain size of less than 2 &mgr;m.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: March 19, 2002
    Assignee: Zimmer Aktiengesellschaft
    Inventors: Brigitta Otto, Ulrich Thiele, Jens Schiebisch