Abstract: The present invention relates to an optical article comprising a birefringent liquid crystal composition, said composition comprising more than 30% by weight based on the total weight of the composition of tolane compounds of formula R—S—Z1-A-Z2—NCS, in which R is a substituted or unsubstituted, linear or branched alkyl group, Z1 and Z2 are aryl groups, and A is an ethynyl group, an arylethynyl group or an ethynylarylethynyl group.

Abstract: The present invention relates to an optical article comprising a birefringent liquid crystal composition, said composition comprising more than 30% by weight based on the total weight of the composition of tolane compounds of formula R—S—Z1-A-Z2—NCS, in which R is a substituted or unsubstituted, linear or branched alkyl group, Z1 and Z2 are aryl groups, and A is an ethynyl group, an arylethynyl group or an ethynylarylethynyl group.

Abstract: A novel liquid crystalline carbonate and the mixture containing the same: wherein R3 is an alkyl (H2n+1Cn) or an alkenyl (H2n?1Cn) group, each of 1 to 12 carbon atoms, the ring A is laterally unsubstituted benzene or pyridine or pyrimidine or trans-substituted cyclohexane ring, symbol r is 0 to 2; the lateral substituents: X2, X3, X4 and X5 in the benzene rings represent independently hydrogen or fluorine or chlorine atoms, X1 is hydrogen or fluorine atom and simultaneously at least one of the substituents: X2, X3 and X4 is fluorine or chlorine atoms, Y is an alkyl or an alkyloxy or an alkenyl or an alkenyloxy group, each of 1 to 12 carbon atoms or hydrogen or fluorine or chlorine atom or NCS group are described.

Abstract: A novel liquid crystalline carbonate and the mixture containing the same: wherein R3 is an alkyl (H2n+1Cn) or an alkenyl (H2n?1Cn) group, each of 1 to 12 carbon atoms, the ring A is laterally unsubstituted benzene or pyridine or pyrimidine or trans-substituted cyclohexane ring, symbol r is 0 to 2; the lateral substituents: X2, X3, X4 and X5 in the benzene rings represent independently hydrogen or fluorine or chlorine atoms, X1 is hydrogen or fluorine atom and simultaneously at least one of the substituents: X2, X3 and X4 is fluorine or chlorine atoms, Y is an alkyl or an alkyloxy or an alkenyl or an aikenyloxy group, each of 1 to 12 carbon atoms or hydrogen or fluorine or chlorine atom or NCS group are described.

Abstract: The present invention relates to low viscosity, broad range nematic media having large birefringence and moderately large dielectric anisotropy. The nematic media are useful in a variety of electrooptical devices, including electronic lenses.

Abstract: The racemic and chiral compounds expressed by common formula 1 and formula 2: wherein the lateral substituents X1, X2, X3, X4, X5, X6, X7 and X8 in the benzene rings represent independently hydrogen and fluorine atoms, bridge group Z represent independently the single bond or COO, CH2CH2, CH2O and OCH2 group, substituent Y represents CH3, or CH2F, CHF2, CF3, C2H5 group, symbols n, m, r and t are independently integers of 1 to 8; symbols p and s signify independently number of 0 to 1 and its orthoconic antiferroelectric long helical pitch mixtures prepared by the methods 1) to the racemic components selected from compounds 1 are added chiral components selected from the compound of formula 1 and/or chiral components selected from the compounds of formula 2 and/or another optically active compounds with high helical twisting power, 2) to chiral compound 1 which helical pitches increases with the temperature increase is added chiral compound 1 which helical pitch decreases with temperature increase.

Abstract: The racemic and chiral compounds expressed by common formula 1 and formula 2: wherein the lateral substituents X1, X2, X3, X4, X5, X6, X7 and X8 in the benzene rings represent independently hydrogen and fluorine atoms, bridge group Z represent independently the single bond or COO, CH2CH2, CH2O and OCH2 group, substituent Y represents CH3, or CH2F, CHF2, CF3, C2H5 group, symbols n, m, r and t are independently integers of 1 to 8; symbols p and s signify independently number of 0 to 1 and its orthoconic antiferroelectric long helical pitch mixtures prepared by the methods 1) to the racemic components selected from compounds 1 are added chiral components selected from the compound of formula 1 and/or chiral components selected from the compounds of formula 2 and/or another optically active compounds with high helical twisting power, 2) to chiral compound 1 which helical pitches increases with the temperature increase is added chiral compound 1 which helical pitch decreases with temperature increase.