Patents by Inventor Dietmar Wewers

Dietmar Wewers 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: 4963438
    Abstract: A method is disclosed for coating sheet-like supports by applying curable organopolysiloxanes, which have been modified with (meth)-acrylate ester groups, on the surface of the support and curing the modified organopolysiloxanes by the action of polymerizing high-energy radiation. Polysiloxanes with hydroxy-functional groups are employed for this purpose, which are obtained by reaction with, based on the hydroxyl groups, 0.4 to 0.9 molar amounts of (meth)acrylic acid and up to 0.6 molar amounts of monocarboxylic acids, which are free of double bonds (sum of the acids.ltoreq.1 molar).
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: October 16, 1990
    Assignee: Th. Goldschmidt AG
    Inventors: Christian Weitemeyer, Dietmar Wewers, Juergen Jachmann
  • Patent number: 4929051
    Abstract: The present invention is directed to an optical glass fiber with a primary coating of organo-polysiloxanes containing acrylic acid ester groups which coating is inter alia hydrolysis stable and rapidly curable.
    Type: Grant
    Filed: March 25, 1988
    Date of Patent: May 29, 1990
    Assignee: Siemens Aktiengesellschaft
    Inventors: Wolfgang Rogler, Christian Weitemeyer, Dietmar Wewers, Frederic Zapf, Bernhard Stapp
  • Patent number: 4908274
    Abstract: Polysiloxanes with (meth)acrylate ester groups linked over SiC groups are disclosed which are obtainable by the reaction of epoxy-functional polysiloxanes of the general formula ##STR1## in which R.sup.1 are the same or different low molecular alkyl groups with 1 to 4 carbon atoms or phenyl groups,R.sup.2 is the same as R.sup.1 or presents the R.sup.3 group 70 to 100% of the R.sup.3 groups being epoxy functional groups and 30 to 0% being alkyl groups with 2 to 20 carbon atoms or hydrogen, with the proviso that the average molecule contains at least 1.5 epoxy groups,a has a value of 1 to 1,000 andb a value of 0 to 10;with such amounts of an acid mixture, comprising(a) 10 to 90 mole percent of (meth)acrylic anhydride and(b) 90 to 10 mole percent of (meth)acrylic acid,that the sum of (a) and (b) adds up to 100 mole percent, and that there are present 0.8 to 1.9n and preferably 1.1 to 1.9n acid equivalents per n epoxide equivalents.
    Type: Grant
    Filed: February 1, 1988
    Date of Patent: March 13, 1990
    Assignee: Th. Goldschmidt AG
    Inventors: Jurgen Jachmann, Christian Weitemeyer, Dietmar Wewers
  • Patent number: 4816541
    Abstract: A method is disclosed for the synthesis of SiH-containing organopolysiloxanes from the corresponding Si-halogen-containing organopolysiloxanes by the reaction with metal hydrides in a liquid reaction medium. The method has the following combiniation of characteristics:(a) the use of a metal hydride being LiH, NaH, KH, CaH.sub.2 or MgH.sub.2 ;(b) the use of ethers as reaction medium;(c) the continuous removal of the metal halide depositing on the surface of the metal hydride particles during the reaction by the action of mechanical energy or ultrasound with formation of a fresh surface.The reaction proceeds practically quantitatively and at low temperatures. It can be applied with particular advantage to industrially obtained mixtures of .alpha.,.omega.-dichloroorganopolysiloxanes.
    Type: Grant
    Filed: October 7, 1987
    Date of Patent: March 28, 1989
    Assignee: Th. Goldschmidt AG
    Inventors: Gotz Koerner, Christian Weitemeyer, Dietmar Wewers