A structural interface having an adaptive liquid crystal material that is positioned to receive electromagnetic radiation and adapted to reflect a selective band of the received electromagnetic radiation so as to help with cooling of a structure in the summer and/or heating of the structure in the winter. The adaptive liquid crystal material is designed to change its selective reflection band when exposed to an activating temperature or an activating light or both. Depending on the interior and/or exterior conditions, the adaptive liquid crystal material has one or more selective reflection bands with a peak wavelength selected from the following: within a sunlight wavelength span, outside a thermal infrared wavelength span, outside the sunlight wavelength span, or within the thermal infrared wavelength span. The structural interface may be applied to an exterior or interior surface of a structural envelop or be integrated into a structural envelope material.

The invention relates to bimesogenic compounds of formula I ##STR00001##
wherein R.sup.11, R.sup.12, MG.sup.11, MG.sup.12, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula I in liquid crystal media and particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.

Mesogenic media comprising a first component, component A, consisting of bimesogenic compounds optionally a second component, component B, consisting of nematogenic compounds, and optionally a second or third component, component C, consisting of one or more chiral molecules, is suitable for use in flexoelectric liquid crystal devices.

The invention relates to bimesogenic compounds of formula I

##STR00001##

wherein R.sup.11, R.sup.12, MG.sup.11, MG.sup.12, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula I in liquid crystal media and particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.

The present invention relates to liquid-crystalline media comprising one or more chiral compounds and one or more compounds selected from the group of compounds of formulae I, II and III,

##STR00001##

in which the parameters have the meaning indicated in Claim 1, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

A dioxolane derivative represented by formula (G1) is provided. The explanation of the substituents is given in the specification. The use of the dioxolane derivative enables the production of a liquid crystal composition and a liquid crystal display device including the liquid crystal composition. ##STR00001##

A liquid crystal composition contains an achiral component T and a chiral dopant and exhibiting an optically isotropic liquid crystal phase. The achiral component T contains at least one compound represented by formula (1). ##STR00001##
In formula (1), R.sup.1 is alkyl having 1 to 12 carbons, alkenyl having 2 to 12 carbons, or alkoxy having 1 to 11 carbons, ring A.sup.1 and ring A.sup.2 independently represent one of the following formulae: ##STR00002##
Z.sup.1, Z.sup.2 and Z.sup.3 are independently a single bond, (CH.sub.2).sub.2, COO, CF.sub.2O or CHCH, X.sup.1 is hydrogen, halogen, CF.sub.3, OCF.sub.3 or CN, L.sup.1, L.sup.2, L.sup.3 and L.sup.4 are independently hydrogen or halogen, and i is 0, 1 or 2.

The invention relates to mesogenic media comprising one or more bimesogenic compounds, one or more nematogenic compound, one or more chiral compound and a compound of formula I,

R.sup.11-A.sup.11-(Z.sup.12-A.sup.12).sub.m-AGI

in which, the parameter A.sup.11, A.sup.12, Z.sup.12 and R.sup.11 have one of the meanings as given in claim 1, and to the use of these mesogenic media in liquid crystal devices and in particular in flexoelectric liquid crystal devices, as well as to liquid crystal devices comprising a liquid crystal medium according to the present invention.

There is provided a polymerizable liquid crystal composition that enables a film formed through application of the composition and exposure thereof to heat or active energy rays to have an excellent molecular alignment and reduced haze. There is also provided an optically anisotropic body that is produced by using such a polymerizable liquid crystal composition and that has a good transparency. In particular, the present invention provides a polymerizable liquid crystal composition containing a polymerizable haze-reducing agent and a polymerizable liquid crystal compound. Furthermore, the present invention also provides an optically anisotropic body produced by using the polymerizable liquid crystal composition of the present invention. Using the polymerizable liquid crystal composition of the present invention enables production of an optically anisotropic body having a good transparency; hence, the polymerizable liquid crystal composition is usefully applied to optical materials used in, for example, retardation films.

Provided is a liquid crystal composition. The liquid crystal composition includes 1 to 50 wt % of an achiral smectic liquid crystal, and a remaining amount of a nematic liquid crystal. The nematic liquid crystal includes a negative nematic liquid crystal.