Abstract: Liquid-crystalline compounds of the formula I ##STR1## R is H, an alkyl or alkylene radical, Z.sup.1 and Z are each, independently of one another, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--,--C.tbd.C-- or a single bond, and one of the radicals Z.sup.1 and Z is alternatively --(CH.sub.2).sub.4 -- or --CH.dbd.CH--CH.sub.2 CH.sub.2 --,A is trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O--,A.sup.1 is trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O--, or is 1,4-phenylene which is unsubstituted or monosubstituted or disubstituted by fluorine and/or Cl atoms and in which, in addition, one or two CH groups may be replaced by N,W is --O--,Q is a single bond,m, o, s, r and t are as defined below,Y is F, Cl, OCF.sub.3, CHF.sub.2, OCHF.sub.2 or OCHF, and can be CF.sub.3,are suitable as components for liquid-crystalline media.

Abstract: Benzene derivatives of the formula I ##STR1## in which n is 1 to 7, Q is --CO or --(CH.sub.2).sub.r -- where r is 1 to 5, s is 0, 1 or 2, t is 0 or 1, where s+t.gtoreq.1, X is F, Cl, --CF.sub.3, --CN, --OCF.sub.3 or --OCHF.sub.2, and Y, L and Z are each, independently of one another, H or F.

Abstract: A nematic liquid crystalline medium having at least two liquid crystalline components with at least one being of formula I ##STR1## wherein R is H, a straight-chain alkyl or alkenyl radical having 1 to 15 carbon atoms, it also being possible to replace one or more CH.sub.2 groups in these radicals, independently of one another, by --O--, --S--, ##STR2## --CO--, --CO--O--, --O--CO-- or --O--CO--O-- in such a way that oxygen atoms are not linked directly to one another,Z.sub.1 and Z are each, independently of one another, --CH.sub.2 --CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C-- or a single bond, and one of the radicals Z.sup.1 and Z is alternatively --(CH.sub.2).sub.4 -- or --CH.dbd.CH--CH.sub.2 CH.sub.2 --,A and A.sup.1 are each, independently of one another, trans-1,4-cyclohexylene in which, in addition, one or two non-adjacent CH.sub.

Abstract: The invention relates to the use of chiral and/or achiral compounds, containing at least one structural element from the group comprisingthiazole-2,4-diylthiazole-2,5-diyl1,2,4-thiadiazole-2,5-diyl1,2,4-thiadiazole-3,5-diylas components of media having a smectic liquid-crystalline phase.

Abstract: The invention relates to optically active compounds of the formula I ##STR1## in which R is an alkyl or alkenyl radical having up to 15 carbon atoms which is unsubstituted, monosubstituted by --CN or at least monosubstituted by fluorine or chlorine, it also being possible for a CH.sub.2 group in these radicals to be replaced by --O--, --CO--, --O--CO--, --CO--O-- or --O--CO--O--,A.sup.1 and A.sup.2 are each, independently of one another, a 1,4-phenylene radical, pyridine-2,5-diyl radical, pyrimidine-2,5-diyl radical, pyrazine-2,5-diyl radical, pyridazine-3,6-diyl radical, 1,3,4-thiadiazole-2,5-diyl radical, 1,2,4-thiadiazole-3,5-diyl radical or trans-1,4-cyclohexylene radical, each of which is unsubstituted or substituted by one or two fluorine atoms, and in which, in addition, one or two non-adjacent CH.sub.2 groups may be replaced by --O-- and/or --S--, and/or a CH group,Z.sup.1, Z.sup.2 and Z.sup.3 are each, independently of one another, --CO--O--, --O--CO--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.

Abstract: Optically active nitrogen-containing heterocycles of the formula I according to claim 1 are suitable as components for ferroelectric liquid crystalline materials.

Abstract: The invention relates to halopyridines of the formula I ##STR1## in which L is Cl or F, andR.sup.1, R.sup.2, A.sup.1, A.sup.2, Z.sup.1, Z.sup.2, m and n are as defined in patent claim 1, and the use thereof as components of liquid-crystalline, in particular ferroelectric, media.

Abstract: Benzene derivatives of the formula I ##STR1## in which n is 1 to 7, Q is --CO or --(CH.sub.2).sub.r --, where r is 1 to 5, s is 0, 1 or 2, t is 0 or 1, where s+t.gtoreq.1, X is F, Cl, --CF.sub.3, --CN, --OCF.sub.3 or --OCHF.sub.2, and Y, L and Z are each, independently of one another, H or F.

Abstract: The invention relates to a matrix liquid-crystal display based on the principle of electrically controlled birefringence, havingtwo plane-parallel outer plates, which, together with a frame, form a cell,integrated nonlinear elements for switching individual pixels on the outer plates,a nematic liquid-crystal mixture of negative dielectric anisotropy and high specific resistance which is located in the cell,electrode layers covered by alignment layers on the insides of the outer plates, anda tilt angle between the longitudinal axis of the molecules at the surface of the outer plates and the outer plates of from about 85 degrees to 95 degrees,in which the nematic liquid-crystal mixture contains at least one compound which contains a structural element of the formula 1, 2 or 3 ##STR1## and to a process for the production thereof and to the nematic liquid-crystal mixture it contains.

Abstract: The invention relates to methylenecyclobutane derivatives of the formula I ##STR1## in which R.sup.1, A.sup.1, A.sup.2, Z.sup.1, Z.sup.2, L.sup.1, L.sup.2, X, Y and m are as defined in claim 1, and to the use thereof as a component of liquid-crystalline media for electrooptical displays.

Abstract: The invention relates to fluorophenylpyrimidines of the formula I: ##STR1## where R.sup.1, R.sup.2, A.sup.1,A.sup.2, Q.sup.1, Q.sup.2 and n have the meaning specified in patent claim 1, and to their use as components of liquid-crystalline, in particular ferroelectric, media.

Abstract: The invention relates to a nematic liquid-crystal composition for active matrix displays with high voltage holding ratio and extremely good low temperature stability.

Abstract: The invention relates to the use of trifluorotoluene derivatives of the formula I ##STR1## in which R.sup.1 is alkyl having 1 to 12 carbon atoms in which, in addition, one or more non-neighboring CH.sub.2 groups may be replaced by --O--, --CO--, --O--CO--, --CO--O--, --O--CO--O--, --CH-halogen, --CH--CN-- and/or --CH.dbd.CH--,A.sup.1 and A.sup.2, in each case independently of one another, are 1,4-phenylene in which, in addition, one or more CH groups may be replaced by N, trans-1,4-cyclohexylene in which, in addition, one or two non-neighboring CH.sub.2 groups may be replaced by --O-- and/or --S--, or 1,4-bicyclo(2,2,2)octylene, each of which is unsubstituted or monosubstituted or polysubstituted by halogen, nitrile and/or CH.sub.3,Z.sup.1 and Z.sup.2, in each case independently of one another, are --CO--O--, --O--CO--, --CH.sub.2 O--, --OCH.sub.2 --, --CH.sub.2 CH.sub.2 -- or a single bond, andn is 0 or 1,as components of chiral tilted smectic phases.

Abstract: The invention relates to a nematic liquid-crystal composition for active matrix displays with high voltage holding ratio and extremely good low temperature stability.

Abstract: The invention relates to ferroelectric liquid-crystal displays having improved multiplexing capability.

Abstract: The invention relates to dihalogenobenzene derivatives of the formula IR.sup.1 --A.sup.1 --Z.sup.1 --A.sup.2 --(Z.sup.2 --A.sup.3).sub.n --R.sup.2wherein R.sup.1, R.sup.2, A.sup.1, A.sup.2, A.sup.3, Z.sup.1, Z.sup.2 and n are as defined in the specification.

Abstract: Compounds of the formula IR.sup.1 --A.sup.1 --A.sup.2 --R.sup.2 IwhereinR.sup.1 and R.sup.2 are each alkyl with 1-15 C atoms, and wherein one or two non-adjacent CH.sub.2 groups can also be replaced by --O--, --S--, --CO--, --O--CO--, --CO--O--, --CO--S--, --S--CO--, --CHHalogen--, --CHCN-- and/or --CH.dbd.CH--,A.sup.1 is 1,4-phenylene, trans-1,4-cyclohexylene or a single bond andA.sup.2 is ##STR1## in which Z is --O--CO--, --CO--O--, --S--CO--, --CO--S--, CH.sub.2 O--, --OCH.sub.2 -- or --CH.sub.2 CH.sub.2 --, with the proviso that, if A.sup.1 is a single bond, A.sup.2 is ##STR2## are suitable as components of chirally tilted smectic liquid crystal phases.

Abstract: This invention relates to fluorinated oligophenyls of formula (I), in which a is 0 or 1 and in which the terminal substituents R.sup.1, R.sup.2 and R.sup.3 are each independently an alkyl or alkenyl residue each with up to 15 C atoms, optionally substituted by CN or by at least one halogen atom, and wherein one or more non adjacent CH.sub.2 groups of these residues may be replaced by --O--, --S--, --CO--, --O--CO--, --CO--O--, --O--CO--O-- or --C.tbd.C--, one of the residues R.sup.1 and R.sup.2 may also denote a group of formula (II), any one of the following pairs of lateral substituents are both fluorine: (A, B), (C, D), (D, E), (C, E), (B, C), (D, J), (D, K), (A, C), (C, J), (C', D'), (D', E), (D', A), (C', E), (C', A), (D', J'), (D', K'), (C', J'), (B, G), (A, G), all of the other lateral substituents being hydrogen or fluorine, and to their use as components of liquid crystalline compositions.

Abstract: 2,3-difluorohydroquinone compounds of the formula I ##STR1## in which R.sup.1 and R.sup.2, in each case independently of one another, are alkyl having 1 to 15 C atoms or alkenyl having 3 to 15 C atoms which are unsubstituted, monosubstituted by cyano or at least monosubstituted by fluorine or chlorine, it also being possible for one CH.sub.2 group in these radicals to be replaced by --O--, --CO--, --CO--O--, --O--CO-- or --O--CO--O--,A.sup.1, A.sup.2 and A.sup.3, in each case independently of one another, are(a) trans-1,4-cyclohexylene, in which, in addition, one or two non-adjacent CH.sub.

Abstract: Derivatives of difluorobenzene of the formula IR.sup.1 --(--A.sup.o --).sub.m --Z.sup.1 --A.sup.1 --Z.sup.2 --A.sup.2 --R.sup.2 Iwherein R.sup.1, R.sup.2, A.sup.o, A.sup.1, A.sup.2, Z.sup.1, Z.sup.2 and m have the meaning indicated in patent claim 1, their preparation and their use as components of liquid-crystal media.