A ferroelectric liquid crystal (FLC) material for the deformed helix FLC (DHFLC) electro-optical mode devices and shows optimum electro-optical properties including high tilt angle (>38), and short helix pitch (<120 nm), and spontaneous polarization (>100 nC/cm.sup.2) comprising at least two components, wherein at least one FLC component is a chiral compound of Formula (I): ##STR00001##
particularly: ##STR00002##
wherein W.sub.1 and W.sub.2 are chiral groups with polar substituent at chiral centre, A and B are independently N atom or CH groups providing that at least one of A or B is N atom. Other various groups are as defined herein.

Proposed is a dielectric material of a liquid-crystal polymer composition including a low-dielectric and high-heat-dissipating liquid-crystal-material monomer for a millimeter wave band and a polymer thereof, and more particularly, a liquid-crystal polymer composition including a low-dielectric and high-heat-dissipating liquid-crystal-material monomer for a millimeter wave band and a polymer thereof, the liquid-crystal-material monomer including a mesogen core, a silane-based group, and a polymerization reactive group.

The invention relates to novel polymerizable liquid crystals of formula (I), ##STR00001##
to LCP mixtures comprising these compounds and to their uses for optical and electro-optical devices.

The present invention discloses photosensitive chiral agent compound S, a cholesteric liquid crystal composition containing the photosensitive chiral agent compound S, and the use of the cholesteric liquid crystal composition in a liquid crystal display element and a liquid crystal display. The photosensitive chiral agent compound S has the properties of high HTP value, good solubility, and short switching time. The cholesteric liquid crystal composition comprising the photosensitive chiral agent compound S has high reflectance retention ratio, which ensures RGB color uniformity and does not require complicated pixel design; low viscosity, which ensures compatibility with existing large-scale panel fabrication processes; and fast UV-induced color switching speed, which results in reduced time during the UV process and lowered production costs. The photosensitive chiral agent compound S can be widely used in optical devices such as liquid crystal electronic books and outdoor and vehicle-mounted displays.

##STR00001##

A polymerizable LC material containing one or more reactive mesogenic compounds, one or more chiral compounds and one or more compounds of formula I, ##STR00001##
wherein the individual radicals have one of the meaning as defied herein, is suitable for use in in optical, electro-optical, decorative or security devices. Polymer films with improved thermal and UV stability are obtainable from the polymerizable LC material.