Patents by Inventor Klaus Praefcke

Klaus Praefcke 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: 5969154
    Abstract: A liquid crystalline compound of formula ##STR1## wherein B and D are each independently of the other C.sub.6 -C.sub.24 alkyl, ##STR2## L is ##STR3## methyl or C.sub.10 -C.sub.18 alkyl, wherein R.sub.1 is C.sub.4 -C.sub.18 alkyl, with the proviso that when L is methyl, at least one of B and D is C.sub.6 -C.sub.24 alkyl;R2 is hydrogen, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, halogen, cyano or nitro,R3, R4 and R5 are each independently of one another hydrogen, OR6, SR6, SeR6, --NHR6, --NR6R7, ##STR4## with the proviso that at least one of R3, R4 and R5 is not hydrogen, R6 is C.sub.7 -C.sub.37 alkyl, C.sub.7 -C.sub.37 alkylene or C.sub.5 -C.sub.18 alkyl which is interrupted by 1 to 6 hetero atoms selected from the group consisting of O, S and N,R7 is hydrogen or R9,R8 is hydrogen or C.sub.1 -C.sub.4 alkyl, andR9 is C.sub.1 -C.sub.12 alkyl, C.sub.2 -C.sub.12 alkylene or C.sub.3 -C.sub.12 alkyl which is interrupted by 1 to 6 hetero atoms selected from the group consisting of O, S and N.
    Type: Grant
    Filed: December 10, 1997
    Date of Patent: October 19, 1999
    Assignee: Ciba Specialty Chemicals Corporation
    Inventors: Zhimin Hao, Abul Iqbal, Nancy Tebaldi, Klaus Praefcke
  • Patent number: 4894181
    Abstract: Carbocyclic compounds of the formula I ##STR1## wherein Q is a benzene or cyclohexane ring or a naphthalene system, X is in each case --CH.sub.2 --(CH.sub.2).sub.p -- where it is also possible for one or two non-adjacent CH.sub.2 groups to be replaced by --O--, --S--, --CO--, --O--CO--, --CO--O-- or --CH.dbd.CH--,p is 0, 1 or 2,A.sup.1 and A.sup.2 independently of one another are each a 1,4-phenylene group which is unsubstituted or monosubstituted or polysubstituted by halogen atoms and/or CH.sub.3 groups and/or CN groups and in which it would also be possible for one or more CH groups to be replaced by N atoms, a 1,4-cyclohexylene group wherein it would also be possible for one or two non-adjacent CH.sub.2 groups to be replaced by --O-- and/or --S--, a piperidine-1,4-diyl group or a 1,4-bicyclo[2.2.2]octylene group,Z is --CO--O--, --O--CO--, --O--, --CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.sub.2 --, --CHCN--CH.sub.2 --, --CH.sub.2 --CHCN--, --CH.dbd.CH--, --CH.dbd.N--, --N.dbd.CH--, --NO.
    Type: Grant
    Filed: May 16, 1988
    Date of Patent: January 16, 1990
    Assignee: Merck Patent Gesellschaft Mit Beschrankter Haftung
    Inventors: Klaus Praefcke, Bernd Kohne, Eike Poetsch
  • Patent number: 4877220
    Abstract: Hexasubstituted cyclohexane compounds of the formula I ##STR1## in which Z.sup.1, Z.sup.2, Z.sup.3, X.sup.1, X.sup.2, A.sup.1, A.sup.2 and A.sup.3, p, R.sup.1 and R.sup.2, m and (n+m) have the meanings given in claim 1, are suitable as components of discotic liquid-crystalline phases.
    Type: Grant
    Filed: September 11, 1987
    Date of Patent: October 31, 1989
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Klaus Praefcke, Bernd Kohne, Werner Stephan
  • Patent number: 4758373
    Abstract: Carbocyclic compounds of the formula I ##STR1## wherein Q is a benzene or cyclohexane ring or a naphthalene system,X is in each case --CH.sub.2 --(CH.sub.2).sub.p -- wherein it is also possible for one or two non-adjacent CH.sub.2 groups to be replaced by --O--, --S--, --CO--, --O--CO--, --CO--O-- or --CH.dbd.CH--,p is 0, 1 or 2,A.sup.1 and A.sup.2 independently of one another are each a 1,4-phenylene group which is unsubstituted or monosubstituted or polysubstituted by halogen atoms and/or CH.sub.3 groups and/or CN groups and in which it would also be possible for one or more CH groups to be replaced by N atoms, a 1,4-cyclohexylene group wherein it would also be possible for one or two non-adjacent CH.sub.2 groups to be replaced by --O-- and/or --S--, a piperidine-1,4-diyl group or a 1,4-bicyclo[2.2.2]octylene group,Z is --CO--O--, --O--CO--, --O--, --CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.sub.2 --, --CHCN--CH.sub.2 --, --CH.sub.2 --CHCN--, --CH.dbd.CH--, --CH.dbd.N--, --N.dbd.CH--, --NO.
    Type: Grant
    Filed: March 24, 1986
    Date of Patent: July 19, 1988
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Klaus Praefcke, Bernd Kohne, Eike Poetsch
  • Patent number: 4734522
    Abstract: Six-membered ring compounds of the formula I ##STR1## wherein A is a benzene or cyclohexane ring,X.sup.1 to X.sup.6 independently of one another in each case are H, --OR, --COOR, --SR, --SOR, --SO.sub.2 R or, if A is a cyclohexane ring, also --O--COR, andR is in each case an alkyl group which has up to 15 C atoms and in which one or two CH.sub.2 groups can be replaced by O atoms, at least three of the substituents X.sup.1 to X.sup.6 being other than H,can be used as constituents of discotic liquid-crystal phases for liquid-crystal display elements.
    Type: Grant
    Filed: January 7, 1986
    Date of Patent: March 29, 1988
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Klaus Praefcke, Bernd Kohne, Wadi Poules, Rudolf Eidenschink, Bernhard Scheuble
  • Patent number: 4713196
    Abstract: Polymer compositions exhibiting liquid-crystalline phases contain chemically bonded mesogenic groups of the formula Ia and/or Ib: ##STR1## in which Q.sup.1 is H, alkyl or alkoxy having 1-5 C atoms, F, Cl, Br or CN,X.sup.1 to X.sup.5 each, independently of one another, are H or an alkyl group having up to 15 C atoms, in which it is also possible for one or two non-adjacent CH.sub.2 groups to be replaced by a group from the group comprising --O--, --S--, --O--CO--O--, O--CO--NH--, --CO--, --CO--O--, --CO--S--, --S--CO--, --SO-- and --SO.sub.2 --.Process for the preparation of polymer compositions of this type comprises the polymerization or grafting of suitable monomers.Polymer compositions of this type are used as substrates in electronics for the fiber and foil techniques.
    Type: Grant
    Filed: August 16, 1985
    Date of Patent: December 15, 1987
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Klaus Praefcke, Bernd Kohne, Eike Poetsch, Claus P. Herz
  • Patent number: 4631143
    Abstract: Triphenylene derivatives of the formula I ##STR1## wherein X.sup.1 to X.sup.6 are each, independently of one another, --SH, --SR, --SOR, --SO.sub.2 R or --S--COR, and each R is an alkyl group with up to 20 C atoms, it being possible for one or two CH.sub.2 groups to be replaced by O atoms and/or by unsubstituted or substituted vinylene or vinylidene groups, may be used as components of discotic liquid-crystalline phases.
    Type: Grant
    Filed: December 21, 1984
    Date of Patent: December 23, 1986
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Klaus Praefcke, Bernd Kohne, Wadi Poules, Eike Poetsch
  • Patent number: 4578210
    Abstract: Six-membered ring compounds of the formula I ##STR1## wherein A is a benzene or cyclohexane ring,X.sup.1 to X.sup.6 independently of one another in each case are H, --OR, --COOR, --SR, --SOR, --SO.sub.2 R or, if A is a cyclohexane ring, also --O--COR, andR is in each case an alkyl group which has up to 15 C atoms and in which one or two CH.sub.2 groups can be replaced by O atoms, at least three of the substituents X.sup.1 to X.sup.6 being other than H,can be used as constituents of discotic liquid-crystal phases for liquid-crystal display elements.
    Type: Grant
    Filed: September 13, 1984
    Date of Patent: March 25, 1986
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Klaus Praefcke, Bernd Kohne, Wadi Poules, Rudolf Eidenschink, Bernhard Scheuble
  • Patent number: 4419263
    Abstract: Cyclohexylcarbonitrile derivatives of the formula I ##STR1## wherein Y is ##STR2## X is --COO--, --O--CO, --CH.sub.2 O--, --OCH.sub.2 -- or --CH.sub.2 CH.sub.2 --, and R is alkyl or alkoxy each of 1-12 carbon atoms, with the proviso that Y is not ##STR3## when X is --COO--; and all cyclohexyl rings are trans, are valuable liquid crystalline components.
    Type: Grant
    Filed: January 7, 1982
    Date of Patent: December 6, 1983
    Assignee: Merck Patent Gesellschaft mit beschrankter Haftung
    Inventors: Klaus Praefcke, Dietmar Schmidt, Rudolf Eidenschink