A liquid crystal (LC) medium comprising a polymerizable compound, a process for its preparation, its use for optical, electro-optical and electronic purposes, such as LC displays, including LC displays of the polymer sustained alignment (PSA) type, and LC displays, including PSA displays, comprising the LC medium.

A liquid crystal dielectric applicable to high-frequency electromagnetic wave modulation has a clearing point of the liquid crystal dielectric higher than 110° C., a low-temperature storage temperature lower than −20° C., and an optical anisotropy greater than 0.35. The liquid crystal dielectric includes: one or more compounds selected by general formula I, which occupy 30-80% of the total weight of the liquid crystal dielectric, and one or more compounds selected by general formula II and/or general formula III, which occupy 20-70% of the total weight of the liquid crystal dielectric. The liquid crystal dielectric has good low-temperature stability, high dielectric anisotropy, a high phase width, appropriate rotary viscosity, appropriate optical anisotropy, low dielectric loss, and a low loss tangent, exhibits strong high-frequency electromagnetic wave tuning capability, is specifically suitable for electromagnetic wave modulation in microwave or millimeter wave areas, and has a good application prospect in liquid crystal phase shifters.

##STR00001##

The present invention relates to an optical code including a film of a charge-transfer material, as well as methods thereof. Described herein are optical codes having anisotropic and/or isotropic regions within the film, which can be provided in a pattern that serves as an optical code.

According to one embodiment, a liquid crystal material composition includes a liquid crystal mixture containing at least one kind of each of a first liquid crystalline compound, a second liquid crystalline compound and a third liquid crystalline compound, a polymerization initiator and a monomer compound including acryloyl groups at respective terminals.

Provided are liquid crystal compounds and mixtures incorporating the same. The liquid crystal compounds of the invention generally comprise a cyclopentane group and at least two other rings. In one embodiment, the liquid crystal compounds of the invention comprise a cyclopentane group and at least two other rings, one of which is a fused ring system.

Disclosed is a liquid crystal composition comprising one or more compounds represented by formula I, one or more compounds represented by formula II, and one or more compounds represented by formula III: ##STR00001##
The liquid crystal composition has simultaneously a lower rotary viscosity, a better photoelectric performance, a higher clearing point, a good low temperature performance, and less display defects. Further disclosed is a liquid crystal display element or device comprising the liquid crystal composition.

A highly thermally conductive epoxy compound, and a composition, a material for a semiconductor package, a molded product, an electric and electronic device, and a semiconductor package, each including the highly thermally conductive epoxy compound. The epoxy compound is represented by Chemical Formula 1 below and has at least one mesogenic naphthalene unit.

E.sub.1-M.sub.1-L.sub.1-M.sub.2-L.sub.2-M.sub.3-E.sub.2  Chemical Formula 1

In Chemical Formula 1, at least one of M.sub.1, M.sub.2, or M.sub.3, which are mesogenic units, is a naphthalene unit. M.sub.1, M.sub.2, M.sub.3, L.sub.1, L.sub.2, and E.sub.1 and E.sub.2 are as defined in the detailed description.

The present invention relates to liquid crystalline media comprising one or more naphthothiadiazol derivatives of formula I, ##STR00001##
in which R.sup.11, R.sup.12, A.sup.11, A.sup.12, A.sup.21, A.sup.22, Z.sup.11, Z.sup.12, Z.sup.21, Z.sup.22, W, X.sup.11, X.sup.12, L, r, s and t have the meanings indicated in claim 1, to the use of such liquid crystal media for optical, electro-optical and electronic purposes, in particular in devices for regulating the passage of energy from an outside space into an inside space, for example in windows.

Disclosed is a liquid crystalline epoxy compound wherein an epoxy group is positioned at a side chain of the longer direction of a mesogen group and each of the mesogen group and the epoxy group is connected to the center of the molecular structure through a flexible linkage. Since the liquid crystalline epoxy compound includes an epoxy group positioned at a side chain of the longer direction of a mesogen group and each of the mesogen group and the epoxy group is connected to the center of the molecular structure through a flexible linkage, the interaction between the mesogens in a cured resin product occurs significantly without weakening even after curing, thereby improving the heat conductivity of the resin compound through the active heat transfer between the mesogens.

A liquid-crystalline medium which comprises at least one compound selected from the group of compounds of the formulae IA to IH, ##STR00001##
in which Z.sup.1 denotes a single bond, —CH.sub.2CH.sub.2—, —CH═CH—, —CH.sub.2O—, —OCH.sub.2—, —CF.sub.2O—, —OCF.sub.2—, —COO—, —OCO—, —C.sub.2F.sub.4—, —(CH.sub.2).sub.4—, —CHFCHF—, —CF.sub.2CH.sub.2—, —CH.sub.2CF.sub.2—, —C≡C—, —CF═CF—, —CH═CHCHO— or —CH.sub.2CF.sub.2O—,
and the use thereof for an active-matrix display, in particular based on the VA, PSA, PS-VA, PALC, FFS, PS-FFS, SA-VA, PS-IPS or IPS effect.