Patents by Inventor Klaus P. Stahl

Klaus P. Stahl 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: 5496499
    Abstract: Biphenylylethanes of the formula I ##STR1## in which one of the radicals R.sup.1 and R.sup.2 is X and the other radical R.sup.1 or R.sup.2 is R--Y-- whereX is H, halogen, --CF.sub.3, --OCHF.sub.2, --OCF.sub.3, --CN, --NCS or --NO.sub.2,R is alkyl, fluoroalkyl, alkenyl or oxaalkyl andY is O, S, --CO--O--, --O--CO--, --O--CO--O--, a single bond or--in the case where m=1--alternatively trans-1,4-cyclohexylene or ##STR2## m is 1 or 2, Ph is in each case identical or different radicals selected from the group comprising 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene and 3,5-difluoro-1,4-phenylene,L.sup.3 and L.sup.4 are each H, or one of these radicals is alternatively F,L.sup.1, L.sup.2and L.sup.5 are each H or F, with the proviso that in the case where X=CN or R.sup.1 =--NCS, Y is trans-1,4-cyclohexylene or ##STR3## and/or m=2 and/or one of the radicals L.sup.1, L.sup.2 and L.sup.
    Type: Grant
    Filed: January 12, 1994
    Date of Patent: March 5, 1996
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Eike Poetsch, Volker Meyer, Klaus P. Stahl, Volker Reiffenrath, Ulrich Finkenzeller, Ekkehard Bartmann, Reinhard Hittich, David Coates, Simon Greenfield, Graham Smith, Hans A. Kurmeier, Dieter Dorsch
  • Patent number: 5387369
    Abstract: Supertwist liquid crystal displays having very short switching times are obtained if the nematic liquid crystal mixture contains at least one component chosen from group A consisting of compounds of the formulae AI to AVI: ##STR1## wherein R.sup.1 and R.sup.2 in each case independently of one another are each R and R is alkyl having 1-12 C atoms, wherein one or two non-adjacent CH.sub.2 groups can also be replaced by --O--, --CH.dbd.CH--, --CO--, --O--CO-- or --CO--O--, and up to four other components.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: February 7, 1995
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Georg Weber, Herbert Plach, Takamasa Oyama, Hiroki Yoshitake, Bernhard Scheuble, Reinhard Hittich, Hans A. Kurmeier, Eike Poetsch, Klaus P. Stahl
  • Patent number: 5093026
    Abstract: Biphenylylethanes of the formula I,R.sup.1 --CH.sub.2 --X--(CH.sub.2 CH.sub.2).sub.m --Ph--Ph--CH.sub.2 CH.sub.2 --Ph--Y--CH.sub.2 --R.sup.2 Iin whichR.sup.1 and R.sup.2 are each, independently of one another, alkyl, alkenyl or oxaalkyl having up to 12 C atoms, and one of the radicals R.sup.1 and R.sup.2 is alternatively H,m is 0 or 1,X and Y are each, independently of one another, O, S, CO--O, O--CO, O--CO--O or a single bond, the radical X is alternatively 1,4-phenylene or trans-1,4-cyclohexylene, and the radical Y is alternatively trans-1,4-cyclohexylene, andis 1,4-phenylene, and one or two of the radicals Ph is alternatively 2- or 3-fluoro-1,4-phenylene,with the proviso that, in the case (a) where X=1,4-phenylene and m=1, one or two of the radicals Ph are 2- or 3-fluoro-1,4-phenylene, and (b) in the case where X=trans-1,4-cyclohexylene, m=0 and one or two of the radicals Ph are 2- or 3-fluoro-1,4-phenylene, are suitable as components of liquid-crystalline phases.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: March 3, 1992
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: David I. Bishop, Stephen Lewis, David Coates, Simon Greenfield, Eike Poetsch, Volker Meyer, Klaus P. Stahl, Volker Reiffenrath, Herbert Plach, Reinhard Hittich, Andreas Wachtler