Patents by Inventor Alfred Eitel

Alfred Eitel 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 polyurethane elastomers in which at least two reactant portions are introduced into separate positions of a screw machine
    Patent number: 4250292
    Abstract: The present invention relates to an improved continuous process for the preparation of polyurethane elastomers which are distinguished from the products produced by known processes by increased elasticity, reduced shrinkage, higher rigidity (limit bending stress), improved cold notched bar impact resistance and good thermal stability.
    Type: Grant
    Filed: September 13, 1979
    Date of Patent: February 10, 1981
    Assignee: Bayer Aktiengesellschaft
    Inventors: Georg Niederdellmann, Wilhelm Goyert, Ernst Meisert, Alfred Eitel, Hans Wagner, Hans Hespe
  • Process for the production of polyurethane elastomers
    Patent number: 3963679
    Abstract: The instant invention is directed to the discovery that it is now possible to obtain high quality, elastomeric polyurethanes or polyureas, even when using highly reactive diamines as chain lengthening agents, without the formation of unwanted irregularities, if the mixture of reactants is exposed to a high velocity gradient by means of vigorously mixing kneading elements at an early phase of the reaction while the viscosity of the reaction mixture is still low. Generally, the viscosity is kept between 100 and 1000 poises and preferably between 200 and 700 poises during the action of the high velocity gradient.
    Type: Grant
    Filed: July 17, 1974
    Date of Patent: June 15, 1976
    Assignee: Bayer Aktiengesellschaft
    Inventors: Martin Ullrich, Ernst Meisert, Alfred Eitel