Abstract: Optically active 1,3-dioxolane derivatives which carry a mesogenic radical in the 4-position and have the general formula (I) ##STR1## are suitable for use as doping agents in liquid-crystal mixtures--in particular ferroelectric liquid-crystal mixtures. The symbols in the general formula have the following meanings:R.sup.1 is composed analogously to the part of the general formula on the right-hand side of X or is an alkyl or alkylene radical which can be substituted,R.sup.2, R.sub.3 and R.sup.4 are H or alkyl (R.sup.4 is also alkenyl) which can also be substituted [R.sup.2 and R.sup.3, together with the C(2) of the dioxolane ring are also a cycloaliphatic radical or a keto group], J, l and n are zero, 1 or 2 and k and m are zero or 1, subject to the proviso that, if k is zero n is zero and if n is zero m is zero and 1.ltoreq.J+l+n.ltoreq.3,--A.sup.1, --A.sup.2 and --A.sup.3 are an aromatic, heterocyclic or aliphatic ring system, --M.sup.1 and --M.sup.2 are --CO--O, --0--CO, --CH.sub.2 CH.sub.2, --CH.dbd.

Abstract: A ferroelectric, liquid-crystalline polymer is composed of repeating units of the formula (I) ##STR1## in which Y=H, CH.sub.3 or F,R.sup.1 =a radical having at least two chiral centers such as for example ##STR2## a=2 to 20, preferably 6 to 12, b,c,d,e and f=0 or 1 with the proviso that d+e+f=2 or 3,A.sup.1,A.sup.2 and A.sup.3 =for example, 1,4-phenylene, cyclohexylene or 2,5-pyrimidinediyl,M.sup.2 and M.sup.3 =CO--O, O--CO, CO--S, S--CO, CH.sub.2 --O, O--CH.sub.2, and ##STR3## These liquid-crystalline polymers have short response times and resistance to mechanical stresses.They can be prepared by free-radical polymerization.

Abstract: A ferroelectric, liquid-crystalline polymer is composed of repeating units of the formula I ##STR1## in which Y=H or CH.sub.3a=an integer from 6 to 12M=a group selected from the formulae which follow: ##STR2## in which --R.sup.2 =--CH.sub.3 or --Cl and b=an integer from 1 to 10. The abovementioned polymer has remarkably short response times. The polymer forms, alone or mixed with other LC components, an orthogonal smectic phase. It is possible to use this phase in the electroclinic mode.

Abstract: Optically active oxirane derivatives containing a mesogenic molecular unit are suitable as dopes in liquid-crystal mixtures. They give liquid-crystalline ferroelectric phases having short response times and electroclinic phases having large electroclinic coefficients. A further advantage is that they induce a helix of very small pitch, so that they are also suitable for helix compensation in LC mixtures.

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.

Abstract: Chiral oxazolidinones of the formula (I) or (II) ##STR1## in which R.sup.1 is, for example, a straight-chain or branched alkyl radical having 1 to 16 carbon atoms orR.sup.2 and R.sup.3 are, for example, --H, --CH.sub.3 or phenyl,j, 1 and n are zero, 1 or 2,k and m are zero or 1,A.sup.1, A.sup.2 and A.sup.3 are, for example, phenyl or cyclohexyl,M.sup.1 and M.sup.2 are, for example, COO or CH.sub.2 O, andX is, for example, CH.sub.2 or COO,are suitable as dopes in liquid-crystal mixtures. They result in liquid-crystalline ferroelectric phases having short response times. A further advantage is that the oxazolidinones induce a helix of very low pitch, so that they are also suitable for helix compensation in LC mixtures.

Abstract: A ferroelectric, liquid-crystalline polymer is composed of repeating units of the formula (I) ##STR1## in which Y.sup.1 =H, CH.sub.3 or FY.sup.2 =H or FR.sup.1 = ##STR2## or an achiral alkyl having 2 to 16 carbon atoms, and R.sup.3 =H or CH.sub.3R.sup.2 =CH.sub.3, Cl or CNg and h=an integer from 0 to 10a=2 to 20, preferably 6 to 12b,c,d,e and f=0 or 1, where d+e+f=2 or 3A.sup.1,A.sup.2 and A.sup.3 =for example, 1,4-phenylene in which one or two hydrogen atoms may be substituted by F, Cl and/or CN, 1,4-cyclohexylene andM.sup.1,M.sup.2 and M.sup.3 =for example, CO--O or O--CO.These liquid-crystalline polymers have short response times and high resistance to mechanical stresses. They can be prepared by free-radical polymerization.

Abstract: Ferroelectric, liquid-crystaline polymers contain repeating units of the formula (I) ##STR1## in which the symbols have the following meanings: B=a group having at least one chiral center, of the formula ##STR2## in which R.sup.6, R.sup.7 and R.sup.8 are identical or different and are H, CH.sub.3, OCH.sub.3, F, Cl or Br, and at least one of the groups R.sup.6, R.sup.7 and R.sup.8 must be H and X=H, F, Cl or Br and R.sup.9 =H or C.sub.1 -C.sub.10 -alkyl,Y=H, CH.sub.3 or F,R.sup.1 =for example a straight-chain or branched alkyl having 1 to 16 carbon atomsa=2 to 20, preferably 6 to 12b, c, d, e and f=0 or 1 with the proviso that d+e+f=2 or 3A.sup.1, A.sup.2, A.sup.3 =for example, 1,4-phenylene or 2,5-pyridinediyl,M.sup.1, M.sup.2 and M.sup.3 =for example CO--O, or O--CO, andG=for example, a straight-chain or branched alkylene having 1 to 16 carbon atoms.

Abstract: Chiral substituted tartarimides, a process for their preparation and their use as doping agents in liquid-crystal mixtures.The new chiral N-substituted tartarimides which are esterified on both of the OH groups (pyrrolidinediones) are characterized by the general formula (I) ##STR1## in which the symbols have the following meaning: R.sup.2 denotes linear or branched (C.sub.1 -C.sub.16)-alkyl, it being possible for one or two non-adjacent CH.sub.2 groups to be replaced by O or S, or, if n1=1, also denotes F, Cl, Br or CN,A.sup.1 and A.sup.2 independently of one another denote 1,4-phenylene, diazine-2,5-diyl, diazine-3,6-diyl, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, 1,3-dithiane-2,5-diyl or 1,4-bicyclo(2,2,2)octylene, it being also possible for these groups to be at least monosubstituted by F, Cl, Br, CN and/or (C.sub.1 -C.sub.12)-alkyl (if appropriate one or two non-adjacent CH.sub.2 groups are replaced by O atoms),denotes CO--O, O--CO, CH.sub.2 --CH.sub.2, OCH.sub.2, CH.sub.2 O, CH.dbd.N, N.dbd.CH or N.dbd.

Abstract: Optically active oxirane-2-carboxylic acid esters with a mesogenic molecular component suitable as dopants in liquid-crystal mixtures. They result in liquid-crystalline ferroelectric phases with short switching times and in electroclinic phases with large electroclinic coefficients. A further advantage lies in the fact that they induce a helix with a very small pitch so that they are also suitable for helix compensation in LC mixtures.

Abstract: The new compounds produced from a molecular structural element with two chirality centers and at least one mesogenic structural element are defined by the general formula (I) ##STR1## in which the symbols have the following meaning: Y.sup.1, Y.sup.2, Y.sup.3, Y.sup.4 = in any two cases (a) hydroxy and MC--CO--O or, independently of each other, MC--CO--O and (b), independently of each other (C.sub.1 -C.sub.10)alkoxy, MC denoting the molecular radical of a mesogenic carboxylic acid after splitting off a COOH group, and it being possible for Y.sup.2 and Y.sup.3, in the case of (C.sub.1 -C.sub.10)alkoxy, also to be jointly part of a dioxolane ring, or Y.sup.1 and Y.sup.4 jointly = 0 as part of a tetrahydrofuran ring, and Y.sup.2 and Y.sup.3 = hydroxy and MC--CO--O or, independently of each other, MC--CO--O. Said esters preferably find application as dopants in twistable liquid crystal phases in which they produce temperature compensation and twisting.

Abstract: The new compounds produced from a molecular structural element with two chirality centers and at least one mesogenic structural element are defined by the general formula (I) ##STR1## in which the symbols have the following meaning: Y.sup.1 =H, (C.sub.1 -C.sub.10)alkyl, MC--CH.sub.2 or MC--CO, MC denoting the molecular radical of a mesogenic carboxylic acid after splitting off a COOH group,Y.sup.2 =(C.sub.1 -C.sub.10)alkyl, MC--CH.sub.2 or MC--CO, it being possible for Y.sup.1 and Y.sup.2 to jointly represent a MC--CH group, which is then part of a dioxolane ring,X=COOR.sup.1, CONH.sub.2, CONR.sup.2 R.sup.3 or C.tbd.N,R.sup.1 =(C.sub.1 -C.sub.10)alkyl or MC--CH.sub.2, andR.sup.2, R.sup.3 =H and (C.sub.1 -C.sub.4)alkyl or, independently of each other, (C.sub.1 -C.sub.4)alkyl.Said esters preferably find application as dopants in twistable liquid crystal phases in which they produce temperature compensation and twisting.

Abstract: The novel compounds are chiral esters of .alpha.-substituted phenylalkanoic acids and mesogenic hydroxy compounds, the symbols in the general formula (I) ##STR1## being defined as follows: MO=molecular radical of a mesogenic hydroxy compound MOH after removal of one H, the radical MO being expressed by the general formula (II)R.sup.2 --(A.sup.1).sub.n1 --(B--).sub.n2 (A.sup.2).sub.n3 --O (II)whereR.sup.2 =straight-chain or branched (C.sub.1 -C.sub.12)-alkyl, it being possible for one or two non-adjacent CH.sub.2 groups to be replaced by O and/or S atoms, or, if n1=1, also F, Cl, Br, CN or CF.sub.3,A.sup.1, A.sup.2 =independently of one another 1,4-phenylene, diazine-2,5-diyl, diazine-3,6-diyl, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, 1,3-dithiane-2,5-diyl or 1,4-bicyclo(2,2,2)octylene, it being possible for these groups also to be at least monosubstituted by F, Cl, Br, CN, CF.sub.3 and/or (C.sub.1 -C.sub.12)-alkyl (one or two non-adjacent CH.sub.

Abstract: The new esters derived from a chiral compound containing two OH groups and at least one mesogenic carboxylic acid which have the general formula (I) ##STR1## in which X.sup.1 =O--H or O--CO--(C.sub.1 to C.sub.12)alkyl and X.sup.2 =O--MC or X.sup.1 and X.sup.2 denote O-MC independently of each other, where MC is the molecular radical of a mesogenic monocarboxylic acid after splitting off an OH group.The esters or esters substituted in the aromatic part of the phenolic part preferably find application as an admixture intwistable liquid crystal phases in which they produce a temperature compensation and a high degree of twisting.

Abstract: New anthraquinone dyestuffs of the general formula I ##STR1## wherein Hal is a halogen atom and the two radicals R are each H or NH.sub.2 and the alkyl group has 1-8 C atoms, exhibit a high order parameter and are suitable for use as components of liquid-crystal dielectrics.