Patents by Inventor Britta Michalski

Britta Michalski 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).

  • Chiral azetidinone derivatives, and their use as dopes in liquid-crystal mixtures
    Patent number: 5334328
    Abstract: Azetidinones of the formula I ##STR1## in which, for example, R.sup.1 is an alkyl or alkenyl radical, R.sup.2 and R.sup.3 are hydrogen or an alkyl or alkenyl radical, Z is hydrogen or (pseudo)halogen, A.sup.1, A.sup.2 and A.sup.3 are a ring system, and M is a spacer group, can be added to liquid-crystal mixtures. Even when admixed in small amounts, they cause considerable twist in the cholesteric and smectic C* phase, which can compensate the pitch of another dope or produce a short S.sub.C * pitch.
    Type: Grant
    Filed: June 17, 1992
    Date of Patent: August 2, 1994
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunter Scherowsky, Claas Junghans, Anke Kaltbeitzel, Rainer Wingen, Britta Michalski