There is provided a liquid crystal composition which enables a significant reduction in crystallization temperature as compared with addition of a homolog while having a similar skeleton structure, which has an excellent compatibility, and which enables an increase in the absolute value of negative dielectric anisotropy (Δ∈). The liquid crystal composition contains two or more compounds which each have two to four ring structures between two side chains. At least one of the ring structures is a 2,3-difluorobenzene skeleton. The two side chains are bonded to different ring structures. The positions of the 2,3-difluorobenzene skeletons are different from each other, and the number of the ring structures are the same as each other.

The present invention provides a liquid crystal display device that includes a horizontal alignment film, stabilizes liquid crystal alignment by the PSA technique, can suppress the increase in power consumption, reduction in contrast, and image sticking in display, and has long-term reliability. The present invention is a liquid crystal display device including a pair of substrates, a liquid crystal layer interposed between the pair of substrates, a horizontal alignment film formed on at least one of the pair of substrates, and a polymer layer which is formed on the horizontal alignment film and controls the alignment of adjacent liquid crystal molecules, wherein the polymer layer is formed by the polymerization of at least one or more kinds of monomers added into the liquid crystal layer, and at least one of the one or more kinds of monomers is polymerized by itself functioning as a polymerization initiator by being irradiated with light.

The liquid crystal light modulator includes a first substrate (10) and a second substrate (20) disposed between two polarizers, and a pair of electrode structures (24, 24). The substrates include homeotropic alignment films (12) and (22), and at least one of the substrates has a function of aligning C-directors of liquid crystal molecules along one direction. The one direction forms an azimuth angle in the range of 35 to 55 degrees with the direction of the electric field generated by the pair of electrode structures (24, 24). A liquid crystal composition layer (31) contains a ferroelectric liquid crystal composition having a chiral smectic C phase or a liquid crystal composition that has an achiral smectic C phase and negative dielectric anisotropy. Light transmittance is modulated by the electric field generated by the electrode structures (24, 24) changing the birefringence index of the liquid crystal composition layer (31).

There is provided 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):

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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.

The present invention provides a hybrid ferroelectric discotic liquid crystal solar cell by incorporating an electrolyte composition for improving power conversion efficiency of the solar cell. The hybrid ferroelectric (FE) discotic liquid crystal solar cell comprises a first layer of n-type inorganic semiconductor deposited on conductive fluorine doped tin oxide (FTO) glass plate 101, a second thin layer of light absorbing inorganic sensitizer 103; wherein the inorganic sensitizer strained titania FTO glass-plate acts as a photo anode, a third layer of ferroelectric discotic liquid crystal electrolyte 104 applied between the photo anode and a photo cathode and a fourth layer of reflective platinum deposited FTO glass-plate 105 configured to act as the photo cathode. The ferroelectric discotic liquid crystal electrolyte composition comprises of an achiral HAT6 discotic molecule (2,3,6,7,10,11-Hexakis-hexyloxy triphenylene) and at least two additives, wherein the additives includes tertiary butyl pyridine (t-bPy) and lithium bis(trifluoromethylsulphonyl)imide Li[CF3SO2]2N.

A smectic A composition with the positive dielectric anisotropy exhibiting a monolayer smectic A structure (SmA.sub.1), which shows a phase transition from a smectic A phase to an isotropic phase (SmA-Iso) or a phase transition from a smectic A phase through a nematic phase to an isotropic phase (SmA-N-Iso) and includes at least two fluorinated compounds selected from the families of fluorinated derivatives of biphenyls and terphenyls expressed by the general formulae 1-12.

For ensuring of the high level of the conductivity the composition is doped with the ionic amidynium salts and/or the ionic potassium complexes of the crown ethers wherein the charge on the cation is delocalized. Such a structure of the ionic compound ensures the better solubility in the liquid crystalline fluorinated composition in comparison to that observed for quaternary ammonium salts.

For writing of the information the dynamic scattering effect (DS) was used, where the transition from a opaque (milky) state to a clear (transparent) state or reversal process is obtained by the change of the frequency of a driving alternating electric field.

The modification of the properties of the smectic A composition by adding of further components such as fluorinated four ring liquid crystal compounds or pyrimidine compounds or cyanocompounds is described.

The present invention provides a hybrid ferroelectric discotic liquid crystal solar cell by incorporating an electrolyte composition for improving power conversion efficiency of the solar cell. The hybrid ferroelectric (FE) discotic liquid crystal solar cell comprises a first layer of n-type inorganic semiconductor deposited on conductive fluorine doped tin oxide (FTO) glass plate 101, a second thin layer of light absorbing inorganic sensitizer 103; wherein the inorganic sensitizer strained titania FTO glass-plate acts as a photo anode, a third layer of ferroelectric discotic liquid crystal electrolyte 104 applied between the photo anode and a photo cathode and a fourth layer of reflective platinum deposited FTO glass-plate 105 configured to act as the photo cathode. The ferroelectric discotic liquid crystal electrolyte composition comprises of an achiral HAT6 discotic molecule (2,3,6,7,10,11-Hexakis-hexyloxy triphenylene) and at least two additives, wherein the additives includes tertiary butyl pyridine (t-bPy) and lithium bis(trifluoromethylsulphonyl)imide Li[CF3SO2]2N.

The new LC media exhibit a ferroelectric nematic phase at ambient temperature. They comprise at least one or more compounds selected from each of formula IA, of formula IB and of the group of formulae IC-1/IC-2/IC-3,

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in which the variable groups have the meanings indicated in the text and in the claims. The mixtures are useful for electro-optics, electronics, electro-mechanic and other applications for materials with very high dielectric permittivity and other energy-saving applications.

New classes of thiadiazole and oxadiazole compounds for use in LC mixtures are disclosed. In an embodiment, the new classes of thiadiazoles and oxadiazoles comprise at least one phenyl ring attached to the heterocyclic ring, where no alkyl, alkenyl or alkynyl tails are attached to the phenyl ring, but one alkyl, alkenyl or alkynyl tail is attached to the other end of the molecule, and a fluoro or cyano group appears in the para position of the phenyl ring. These compounds are disclosed as being effective at inducing smectic A phases in liquid crystal mixtures, particularly in liquid crystal mixtures also possessing a smectic C phase, more particularly in materials possessing a chiral smectic C (ferroelectric) phase.

A modulator material layer includes a polymer matrix formed of a plurality of cross-linked polymer molecules and a plurality of droplets of liquid crystals within the polymer matrix. A planar macrocycle dye is dispersed within the plurality of droplets of liquid crystals. The planar macrocycle dye can include one or more of a phthalocanine, a porphyrin, a naphthalocyanine, a metallophthalocyanine, a metalloporphyrin, or a metallonaphthalocyanine.