A liquid crystal medium composition is provided with a negative liquid crystal material; at least one polymerizable monomer which is polymerized under a UV irradiation; and at least one alignment assistant including a polar portion and a non-polar portion. The polar portion is connected with the non-polar portion by a bonding group. The liquid crystal medium composition can achieve the vertical alignment without the PI alignment layer by improving the liquid crystal material.

The present invention relates to a liquid crystal display device that includes a particular color filter containing a material containing chiral liquid crystals and a particular pigment. The present invention provides a liquid crystal display device that can prevent a decrease in the voltage holding ratio (VHR) of a liquid crystal layer and solve the problem of display defects, such as white spots, variations in alignment, and burn-in. Because liquid crystal display devices according to the present invention characteristically prevent a decrease in the voltage holding ratio (VHR) of a liquid crystal layer and reduces the occurrence of display defects, such as burn-in, the liquid crystal display devices are particularly useful as liquid crystal display devices in IPS mode and FFS mode for active-matrix driving and can be applied to household electrical appliances, automobiles, production facilities, measuring and analytical instruments, and communication devices.

The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy, comprising a low-molecular-weight component and a polymerizable component. The polymerizable component comprises self-aligning, polymerizable mesogens (polymerizable self-alignment additives) which effect homeotropic (vertical) alignment of the LC media at a surface or the cell walls of a liquid-crystal display (LC display). The invention therefore also encompasses LC displays having homeotropic alignment of the LC medium without alignment layers. The invention discloses novel structures for self-alignment additives which have a certain position of the functional groups.

Provided is a liquid crystal compound satisfying at least one of physical properties such as high stability to heat and light, a high clearing point (or high maximum temperature), low minimum temperature of a liquid crystal phase, small viscosity, suitable optical anisotropy, large dielectric anisotropy, a suitable elastic constant and excellent compatibility with other liquid crystal compounds, a liquid crystal composition containing the compound and a liquid crystal display device including the composition.

A compound, represented by formula (1):

##STR00001##

wherein, in formula (1), R.sup.1 is alkoxy having 1 to 9 carbons or the like; R.sup.2 is alkenyl having 2 to 10 carbons; Z.sup.1 and Z.sup.2 are independently a single bond, —CH.sub.2CH.sub.2—, —CH═CH— or the like; and a and b are independently 0 or 1.

The liquid crystal composition of the present invention can be used in a liquid crystal display element of an IPS type or a TN type in which display defects such as burn-in and dropping marks in high speed response are unlikely to be generated. Since the liquid crystal composition contains a component which is a dielectrically positive component including a dielectrically positive compound and a dielectrically neutral component of which dielectric anisotropy is greater than −2 and less than +2, the liquid crystal composition has excellent characteristics that the liquid crystal composition has a liquid crystal phase in a wide temperature range, low viscosity, excellent solubility at a low temperature, high specific resistance and a high voltage holding ratio, and is stable with respect to heat and light.

Reactive mesogens (RMs), mixtures and formulations comprising RMs, polymers obtained from such RMs and RM mixtures, and the use of the RMs, RM mixtures and polymers in optical or electrooptical components or devices, like optical films for liquid crystal displays (LCDs).

Provided is an optically anisotropic layer having an excellent surface condition, with which an image display device having an excellent contrast can be manufactured; and an optical film, a polarizing plate, and an image display device, each having the optically anisotropic layer. The optically anisotropic layer is obtained by immobilizing a polymerizable liquid crystal composition including a polymerizable rod-shaped liquid crystal compound exhibiting a liquid crystal state of a smectic phase and an additive in a liquid crystal state of a smectic phase, in which a molecular length A (Å) of the polymerizable rod-shaped liquid crystal compound, a layer interval B (Å) of the smectic phase of the optically anisotropic layer, and a molecular length C (Å) of the additive satisfy a relationship of Expression (1-1), 0.5×B≤C≤0.6×A . . . (1-1).

The present invention discloses a compound of which a structural formula thereof is represented as the following formula: ##STR00001##
The compound disclosed by the present invention can be used as a liquid crystal compound and overcomes the problem that solubility of the traditional dibenzothiophene-class liquid crystals is poor, and thus can be better applied to the liquid crystal material field. The present invention further discloses a liquid crystal medium containing the compound and an application thereof.

Provided are a polymerizable compound having at least one monovalent group (A), a polymerizable composition containing the polymerizable compound, a liquid crystal composite prepared from the polymerizable composition, and a liquid crystal device having the polymerizable composition. ##STR00001## In monovalent group (A), R.sup.1 and R.sup.2 are independently hydrogen, halogen or alkyl having 1 to 20 carbons, and in the alkyl, at least one piece of —CH.sub.2— may be replaced by —O— or —S—, and at least one piece of —(CH.sub.2).sub.2— may be replaced by —CH═CH—, and in the groups, at least one hydrogen may be replaced by halogen.

A liquid-crystalline medium containing one or more compounds of formula IA, ##STR00001##
and the use thereof in an active-matrix display, in particular in a VA, IPS, U-IPS, FFS, UB-FFS, SA-VA, SA-FFS, PS-VA, PS-OCB, PS-IPS, PS-FFS, PS-UB-FFS, PS-posi-VA, PS-TN, polymer stabilised SA-VA or polymer stabilised SA-FFS display.