Patents by Inventor Christine Stemmer

Christine Stemmer 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: 20190106377
    Abstract: A compound of the structural formula 1 Also disclosed is a process for producing 2-(3-(aminomethyl)-3,5,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone nitrile and malononitrile to afford the intermediate 2-(3-cyano-3,5,5-trimethylcyclohexylidene) malononitrile, and B) hydrogenating 2-(3-cyano-3,5,5-trimethylcyclohexylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Application
    Filed: November 1, 2018
    Publication date: April 11, 2019
    Applicant: Evonik Degussa GmbH
    Inventors: Alexander Martin RÜFER, Anne RITTSTEIGER, Jörg-Joachim NITZ, Stephan KOHLSTRUK, Martina ORTELT, Dirk FUCHSMANN, Michael DEMMING, Christine STEMMER, Denise OTT, Anja Poschen
  • Patent number: 10252980
    Abstract: A compound of the structural formula 1 as a hardener in epoxy resin composition.
    Type: Grant
    Filed: November 1, 2018
    Date of Patent: April 9, 2019
    Assignee: EVONIK DEGUSSA GMBH
    Inventors: Alexander Martin Rüfer, Anja Poschen, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott
  • Patent number: 10173979
    Abstract: The present invention relates to 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine, which can be used as hardener in epoxide applications.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: January 8, 2019
    Assignee: Evonik Degussa GmbH
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Patent number: 10160717
    Abstract: A compound of the structural formula 1 A process for producing 2-(3-(aminomethyl)-3,5,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone nitrile and malononitrile to afford the intermediate 2-(3-cyano-3,5,5-trimethylcyclohexylidene)malononitrile, and B) hydrogenating 2-(3-cyano-3,5,5-trimethylcyclohexylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: December 25, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20180093952
    Abstract: The present invention relates to a process for producing 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine, which can be used as hardener in epoxide applications.
    Type: Application
    Filed: December 5, 2017
    Publication date: April 5, 2018
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Patent number: 9868702
    Abstract: A process for producing 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine by A) reacting triacetonamine (TAA) and malononitrile to afford the intermediate 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile, and B) hydrogenating 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar. In another embodiment, the hydrogenation in step B) of the process is performed in two stages at 20-120° C. and at 20-300 bar.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: January 16, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Patent number: 9862673
    Abstract: A diamine 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine of formula 1 and a process for producing 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone (IP) and malononitrile to afford the intermediate 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile, and B) hydrogenating 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Grant
    Filed: May 25, 2017
    Date of Patent: January 9, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20170355661
    Abstract: A diamine 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine of formula 1 and a process for producing 2-(3,3,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone (IP) and malononitrile to afford the intermediate 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile, and B) hydrogenating 2-(3,5,5-trimethylcyclohex-2-en-1-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Application
    Filed: May 25, 2017
    Publication date: December 14, 2017
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20170355674
    Abstract: A process for producing 2-(2,2,6,6-tetramethylpiperidin-4-yl)propane-1,3-diamine by A) reacting triacetonamine (TAA) and malononitrile to afford the intermediate 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile, and B) hydrogenating 2-(2,2,6,6-tetramethylpiperidin-4-ylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar. In another embodiment, the hydrogenation in step B) of the process is performed in two stages at 20-120° C. and at 20-300 bar.
    Type: Application
    Filed: May 25, 2017
    Publication date: December 14, 2017
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch
  • Publication number: 20170355662
    Abstract: A compound of the structural formula 1 Also disclosed is a process for producing 2-(3-(aminomethyl)-3,5,5-trimethylcyclohexyl)propane-1,3-diamine by A) reacting isophorone nitrile and malononitrile to afford the intermediate 2-(3-cyano-3,5,5-trimethylcyclohexylidene)malononitrile, and B) hydrogenating 2-(3-cyano-3,5,5-trimethylcyclohexylidene)malononitrile in the presence of at least one catalyst. In another embodiment, the hydrogenation in step B) of the process is performed at 20-120° C. and at 20-300 bar.
    Type: Application
    Filed: May 25, 2017
    Publication date: December 14, 2017
    Inventors: Alexander Martin Rüfer, Anne Rittsteiger, Jörg-Joachim Nitz, Stephan Kohlstruk, Martina Ortelt, Dirk Fuchsmann, Michael Demming, Christine Stemmer, Denise Ott, Anja Stasch