Abstract: Optically active compounds of the formula ##STR1## wherein n stands for the number 0 or 1; Z.sup.1 is a single covalent bond or --CH.sub.2 CH.sub.2 --; Z.sup.2 is a single covalent bond, --CH.sub.2 CH.sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, --COO-- or --OOC--; rings A.sup.1 and A.sup.2 each independently represent trans-1,4-cyclohexylene or optionally halogen-, cyano- and/or methyl-substituted 1,4-phenylene in which optionally 1 CH group or 2 CH groups is/are replaced by nitrogen; R.sup.2 is a group R.sup.4 or a group of the formula ##STR2## R.sup.4 is cyano, halogen, --OCY.sup.1 F.sub.2, --CY.sup.1 F.sub.2 or an alkyl group in which optionally one >CH--CH< is replaced by >C.dbd.C< and/or optionally one methylene group or two non-adjacent methylene groups is/are replaced by --O--, --COO-- and/or --OOC-- and/or optionally one methylene group is replaced by --CHY.sup.2 --; Y.sup.1 is hydrogen or fluorine; Y.sup.2 is halogen, cyano or methyl; R.sup.1 and R.sup.

Abstract: A liquid crystal cell comprising a cholesteric liquid crystal (3) between parallel plates (1, 2) as used e.g. for optical filters. The previously unavoidable interference through faulty disinclination is eliminated in that the cholesteric liquid crystal is mixed with a nematic or smectic liquid crystal material having negative dielectric anisotropy and the cell is subjected to an electric field directed at right angles to the plates.

Abstract: A chiral dopant of the formula ##STR1## wherein ring A is 1,4-phenylene which is optionally substituted with one or more fluorine atoms, chlorine atoms, bromine atoms, cyano groups, or methyl groups, and in which one or two CH groups can be replaced by nitrogen, or is trans-1,4-cyclohexylene;Z is a single covalent bond, --CH.sub.2 CH.sub.2 --, --CH.sub.2 O-- or --OCH.sub.2 --;X.sup.1,X.sup.2,X.sup.3,X.sup.4 each independently are hydrogen or fluorine;R.sup.1 is hydrogen, is alkyl with 1 to 12 carbon atoms which is optionally substituted with one or more fluorine or chlorine atoms and in which one or two non-adjacent CH.sub.2 groups can be replaced by --O--, is alkenyl with 2 to 12 carbon atoms, which is optionally substituted with one or more fluorine or chlorine atoms and in which one or two non-adjacent CH.sub.2 groups can be replaced by --O--, is a group of the formula ##STR2## and when R.sup.1 is bonded to an aromatic ring, can also be fluorine, chlorine, cyano, CF.sub.3, OCHF.sub.2 or --OCF.sub.3 ;R.sup.

Abstract: Optically active compounds of the formula ##STR1## wherein rings A, B and C each independently are unsubstituted or each are 1,4-phenylene substituted with at least one of halogen-, cyano-, methyl- or methoxy in which optionally 1 CH group or 2 CH groups is/are replaced by nitrogen; R.sup.1 is a radical of an optically active terpene alcohol after cleavage of the hydroxy group or a group --(CH.sub.2).sub.m --C*HX.sup.1 --R.sup.3 ; R.sup.2 is a radical of an optically active terpene alcohol after cleavage of the hydroxy group or a group --(CH.sub.2).sub.n --C*HX.sup.2 --R.sup.4 ; m and n each independently stand for the number 0 or 1: C* denotes a chiral carbon atom; X.sup.1 and X.sup.2 each independently are fluorine, chlorine, cyano, methyl or methoxy; R.sup.3 and R.sup.4 each independently denote a group R, phenyl or phenyl substituted with R, with the proviso that R.sup.3 is different from X.sup.1 and R.sup.4 is different from X.sup.

Abstract: Compounds containing a 4-[(E)-alk-2-enoyloxy]benzoate group and liquid crystalline mixtures which contain such compounds and the use of such compounds and, respectively, mixtures in electro-optical indicating devices.The compounds are of the formula ##STR1## wherein R.sup.1 is alkyl with 1 to 12 carbon atoms;X.sup.1, X.sup.3 each independently are halogen or hydrogen; andX.sup.2 is halogen or cyano.

Abstract: Compounds of the formula ##STR1## wherein rings A, B and C, Z.sup.1, Z.sup.2, Z.sup.3, R.sup.1, R.sup.2 and R.sup.3 are defined in the specification, their manufacture, liquid crystalline mixtures which contain such compounds and the use of these compounds for electro-optical purposes.

Abstract: Compounds of the formula ##STR1## wherein X.sup.1 denotes fluorine or chlorine and X.sup.2 denotes hydrogen, fluorine or chlorine; R.sup.1 is 3E-alkenyl, 4-alkenyl, 2E-alkenyloxy or 3-alkenyloxy; n stands for the number 0 or 1; one of the groups Y.sup.1 and Y.sup.2 is a single covalent bond, --COO--, --OOC--, --CH.sub.2 CH.sub.2 --, --CH.sub.2 O-- or --OCH.sub.2 -- and the other of the groups Y.sup.1 and Y.sup.2 is a single covalent bond; and rings A.sup.1 and A.sup.2 each individually are substituted or unsubstituted trans-1,4-cyclohexylene, in which optionally 2 non-adjacent CH.sub.2 groups are replaced by oxygen, or substituted or unsubstituted 1,4-phenylene, in which optionally 1 CH group or 2 CH groups is/are replaced by nitrogen; with the proviso that X.sup.2 denotes fluorine or chlorine and/or Y.sup.1 or Y.sup.2 denotes --CH.sub.2 O-- or --OCH.sub.2 -- when simultaneously X.sup.1 is fluorine and R.sup.1 is 3E-alkenyl,and their use for liquid crystalline mixtures and electro-optical purposes.

Abstract: Polymeric coatings having optically non-linear or optically anisotropic properties in selected areas and of any arbitrary shape including a pattern. These zones are sharply defined from surfaces having centro-symmetrical or isotropic configurations or from surfaces with different optically non-linear or anisotropic properties. The polymeric coating has optically non-linear and/or mesogenic side chains, selected surface areas of which are cross-linked by the action of light, the zones which have optically non-linear or anisotropic properties being subjected to the influence or orienting fields or forces during the cross-linking process. The distances between optically different zones are limited to typically about 1 .mu.m.

Abstract: The present invention provides compounds of the general formula: ##STR1## wherein R is an alkyl group with 1 to 12 carbon atoms or a group of the formula ##STR2## Ring A.sup.1 is 1,4-phenylene, which is unsubstituted or substituted with fluorine, pyridine-2,5-diyl or pyrimidine-2,5-diyl;Ring A.sup.2 is trans-1,4-cyclohexylene or trans-1,3-dioxane-2,5-diyl;R.sup.1 is an alkyl, alkenyl or alkoxyalkyl group with 1 to 12 and, respectively, 2 to 12 carbon atoms;X.sup.1 is fluorine, chlorine, bromine, trifluoromethyl, trifluoromethoxy or difluoromethoxy; andX.sup.2, X.sup.3 each independently are hydrogen or fluorine.The invention is also concerned with liquid crystal mixtures which contain these compounds and with the use of these compounds and mixtures for electro-optical purposes.

Abstract: Compounds of the general formula ##STR1## wherein R.sup.1 represents vinyl or straight-chain alkenyl with 3 to 7 carbon atoms,the manufacture of such compounds, liquid crystalline mixtures which contain such compounds as well as the use of such compounds for electro-optical purposes.

Abstract: Compounds of the formula ##STR1## wherein ring A is trans-1,4-cyclohexylene, 1,4-phenylene, pyrimidine-2,5-diyl or trans-1,3-dioxane-2,5-diyl; n is either 0 or 1; ring B stands for 1,4-phenylene or trans-1,4-cyclohexylene; and R.sup.1 is 3E-alkenyl or on a saturated ring also 1E-alkenyl, their manufacture, liquid crystalline mixtures which contain these compounds as well as their use for electro-optical purposes.

Abstract: Fluoro-substituted phenyl-cyclohexylacetylenes have the formula: ##STR1## wherein R signifies alkyl, alkoxy, alkenyl or alkenyloxy with 1 or, respectively, 2 to 12 carbon atoms in which one CH.sub.2 group can be replaced by oxygen and/or one or more hydrogen atoms can be replaced by fluorine atoms, with the proviso that two oxygen atoms are not directly adjacent;A.sup.1 represents 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, trans-1,4-cyclohexylene or trans-1,3-dioxane-2,5-diyl;A.sup.2 signifies trans-1,4-cyclohexylene or 1,4-phenylene which is optionally substituted with fluorine;Z.sup.1 signifies a single covalent bond, --CH.sub.2 CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 O--, --(CH.sub.2).sub.4 --, --O(CH.sub.2).sub.3 --, --(CH.sub.2).sub.3 O-- or, when ring A.sup.1 represents a saturated ring, also the trans form of --CH.dbd.CH(CH.sub.2).sub.2 -- or --CH.dbd.CHCH.sub.2 O--;Z.sup.2 signifies a single covalent bond, --CH.sub.2 --CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 O--, --(CH.sub.2).sub.

Abstract: The present invention is concerned with novel chlorophenylalkoxyalkyl compounds of the general formula ##STR1## wherein R denotes an alkyl residue with 1 to 12 carbon atoms; n is a whole number of 2 to 7, ring A denotes trans-1,4-cyclohexylene or 1,4-phenylene; m is either 0 or 1; ring B is trans-1,4-cyclohexylene, 1,4-phenylene in which optionally one CH group or two non-adjacent CH groups is/are replaced by nitrogen or, when m stands for 1, also trans-1,3-dioxane-2,5-diyl; Y.sup.1 and Y.sup.2 each independently represent a single covalent bond or --CH.sub.2 CH.sub.2 --; and X denotes hydrogen, fluorine or chlorine, their manufacture, liquid crystalline mixtures which contain these compounds, their production and use for electro-optical purposes.

Abstract: An oriented photopolymer is a polymer where photomodification is initiated by irradiation with plane-polarized light and where the molecular configuration has a preferred orientation as a result of linear polarization. These polymers have optically anisotropic and other novel properties.

Abstract: Compounds having the Formula: ##STR1## wherein R.sup.1 denotes an alkenyl group;A.sup.1 and A.sup.2 each independently represent 1,4-phenylene, which is unsubstituted or substituted with halogen and in which, when it is unsubstituted, optionally 1 or 2 CH group(s) is/are replaced by nitrogen, or trans-1,4-cyclohexylene or trans-1,3-dioxane-2,5-diyl;Z.sup.1 and Z.sup.2 each independently signify a single covalent bond, --CH.sub.2 CH.sub.2 --, --COO--, --OOC--, --OCH.sub.2 --, --CH.sub.2 O--, --C.dbd.C--, --(CH.sub.2).sub.4 --, --O(CH.sub.2).sub.3 --, --(CH.sub.2).sub.3 O-- or the trans form of --OCH.sub.2 CH.dbd.CH--, --CH.dbd.CHCH.sub.2 O--, --(CH.sub.2).sub.2 CH.dbd.CH-- or --CH.dbd.CH(CH.sub.2).sub.2 --;n is either 0, 1 or 2; andR.sup.2 is halogen, cyano or alkyl with 1 to 12 carbon atoms, which is optionally substituted with fluorine and in which optionally 1 --CH.sub.2 -- group or 2 non-adjacent --CH.sub.2 -- groups is/are replaced by oxygen, --COO--, --OOC--, --CO-- and/or a --CH.sub.2 --CH.sub.

Abstract: Compounds of the general formula ##STR1## wherein ring A represents 1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, trans-1,4-cyclohexylene or trans-1,3-dioxane-2,5-diyl;Z signifies a single covalent bond, --CH.sub.2 CH.sub.2 --, --OCH.sub.2 --, --CH.sub.2 O--, --(CH.sub.2).sub.4 --, --O(CH.sub.2).sub.3 --, --(CH.sub.2).sub.3 O-- or, where ring A represents a saturated ring, also the trans form of --CH.dbd.CH(CH.sub.2).sub.2 -- or --CH.dbd.CHCH.sub.2 O--;X signifies fluorine, chlorine, cyano, --CF.sub.3, --OCF.sub.3 or --OCHF.sub.2 ;Y.sup.1, Y.sup.2 each independently signify fluorine or hydrogen; andR signifies alkyl, alkoxy, alkenyl or alkenyloxy with 1 or, respectively, 2 to 12 carbon atoms in which one CH.sub.2 group or two non-adjacent CH.sub.

Abstract: Compounds of general formula (I), wherein R signifies hydrogen, halogen, cyano, isothiocyanato, or alkyl, alkenyl or alkynyl with 1 to 15 carbon atoms, which is unsubstituted or substituted with at least one of halogen, cyano and/or trifluoromethyl and in which one or more non-adjacent --CH.sub.2 -- group(s) can be replaced by --O--, --S--, --CO--, --COO-- and/or --OOC--; Q represents alkylene with 2 to 10 carbon atoms, which is unsubstituted or substituted with at least one fluorine and in which one --CH.sub.2 -- group can be replaced by --O--, --S--, --COO--, or --OOC--, or --CH.sub.2 --, --CF.sub.2 --, --CHF-- or a single covalent bond; A.sup.1, A.sup.2, A.sup.

Abstract: An optical frequency conversion element has a wave-guiding layer which consists of a .chi..sup.(2) -active ferroelectric liquid crystal. The monomeric or polymeric liquid crystal material has a periodic structure which permits the so-called quasi phase matching of a guided laser beam. The period length of the structure is equal to twice the coherence length l.sub.c =.pi./.DELTA..beta. of the material, whereby .DELTA..beta.=.beta..sub.o (2.omega.)-2.beta..sub.o (.omega.), with .omega.=angular frequency of the fundamental wave, 0=zero-order mode and .beta.=propagation constant of the mode.

Abstract: Compounds of the formula ##STR1## and liquid crystalline mixtures containing same.

Abstract: Compounds of the general formula ##STR1## wherein R.sup.1 is C.sub.5-12 -alkyl or C.sub.5-12 -alkenyl;R.sup.2 is C.sub.1-9 -alkyl or C.sub.2-9 -alkenyl; provided that at least one of groups R.sup.1 and R.sup.2 is alkenyl;X is a CH group or nitrogen;n is either 0 or 1;q is a whole number between 2 to 6 inclusive;r is either 0 or 1 provided that the sum of q and r at least 3,s is either 0 or 1; andp is either 1 or 2, provided that n is zero when p is 2;mixtures which contain these compounds as well as the use of these compounds for electro-optical purposes.