Patents by Inventor Frank-Stefan STERN

Frank-Stefan STERN 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).

  • Publication number: 20210155747
    Abstract: The present invention relates to the use of tertiary amines as catalysts for the cross-linking of isocyanate groups which are aliphatically and/or cyclo-aliphatically bonded. The catalysts according to the invention have the particular advantage that they are thermally latent.
    Type: Application
    Filed: April 12, 2019
    Publication date: May 27, 2021
    Inventors: Richard Meisenheimer, Paul Heinz, Dirk Achten, Frank-Stefan Stern
  • Patent number: 11000976
    Abstract: The invention relates to a process for producing an optical casting comprising at least one volume-holographic optical element by means of at least one casting operation, the process comprising the following steps: providing a casting mould comprising a first mould section having a flat, spherical, aspherical or free-form first surface and a second mould section having a flat, spherical, aspherical or free-form second surface, the first mould section being connectable to the second mould section to form the casting mould, providing at least one holographic optical element, positioning and aligning the at least one holographic optical element with respect to the first mould section or/and with respect to the second mould section, combining the first and second mould sections to form the casting mould, introducing casting material in one or more casting steps, the casting material having a maximum viscosity at 25° C.
    Type: Grant
    Filed: January 13, 2016
    Date of Patent: May 11, 2021
    Assignee: Covestro Deutschland AG
    Inventors: Thomas Fäcke, Robert Maleika, Enrico Orselli, Frank-Stefan Stern
  • Publication number: 20180009931
    Abstract: A composition comprising an isocyanate component A) comprising at least one cycloaliphatic or araliphatic diisocyanate, a polyol component B) comprising at least one polyol having an OH number of 80 to 1000 mg KOH/g, an additive component C) comprising at least one internal demoulding agent, and a catalyst component D) comprising at least one inorganic metal complex as thermally latent catalyst, characterized in that the thermally latent catalyst has a quotient of reaction rates between catalysed reaction and uncatalysed reaction at 30° C. of =5.0 and at 60° C. of =1.1. The present invention further provides a process for producing an elastomer and for the use of the composition for production of transparent shaped bodies.
    Type: Application
    Filed: January 13, 2016
    Publication date: January 11, 2018
    Inventors: Robert MALEIKA, Frank-Stefan STERN, Frank RICHTER, Dorota GRESZTA-FRANZ, Hans-Josef LAAS
  • Publication number: 20170368723
    Abstract: The invention relates to a process for producing an optical casting comprising at least one volume-holographic optical element by means of at least one casting operation, the process comprising the following steps: providing a casting mould comprising a first mould section having a flat, spherical, aspherical or free-form first surface and a second mould section having a flat, spherical, aspherical or free-form second surface, the first mould section being connectable to the second mould section to form the casting mould, providing at least one holographic optical element, positioning and aligning the at least one holographic optical element with respect to the first mould section or/and with respect to the second mould section, combining the first and second mould sections to form the casting mould, introducing casting material in one or more casting steps, the casting material having a maximum viscosity at 25° C.
    Type: Application
    Filed: January 13, 2016
    Publication date: December 28, 2017
    Inventors: Thomas FÄECKE, Robert MALEIKA, Enrico ORSELLI, Frank-Stefan STERN
  • Publication number: 20170029552
    Abstract: The invention relates to a composition for producing transparent polythiourethane bodies, containing or consisting of A) a polyisocyanate component that contains at least one polyisocyanate having an isocyanate group functionality of at least 2 per molecule, B) a thiol component that contains at least one polythiol having a thiol group functionality of at least 2 per molecule, and if appropriate, C) auxiliary and additional agents, the ratio of isocyanate groups to groups that are reactive to isocyanates being between 0.5:1 to 2.0:1, and said composition being characterised in that it also contains D) at least one aromatic nitrile. The invention also relates to a method for producing transparent polythiourethane bodies by reacting such a composition, to the polythiourethane bodies produced in this manner, to the use of aromatic nitriles for producing transparent polythiourethane bodies, and to a mixture of a polyisocyanate and an aromatic nitrile.
    Type: Application
    Filed: April 13, 2015
    Publication date: February 2, 2017
    Inventors: Robert MALEIKA, Fredie LANGENSTUECK, Christoph EGGERT, Irene C. LATORRE MARTINEZ, Frank-Stefan STERN, Josef SANDERS