The present invention relates to a liquid crystal (LC) medium comprising polymerisable compounds, to a process for its preparation, to its use for optical, electro-optical and electronic purposes, in particular in LC displays, and to LC displays comprising it.

A liquid crystal composition includes one or more compounds represented by Chemical Formula 1. ##STR00001## In Chemical Formula 1, ##STR00002##
are a cyclohexane or tetrahydropyran, and R1 and R2 are each independently hydrogen, a C1 to C8 alkyl group, a C2 to C8 alkenyl group, or a C1 to C8 alkoxy group.

The present invention provides a novel non-lamellar liquid crystal-forming composition. An aspect of the present invention is a non-lamellar liquid crystal-forming composition comprising a fatty acid ester and a phospholipid. The fatty acid ester has a hydrophilic group having one hydroxyl group or a salt thereof, and the fatty acid ester is a fatty acid ester having none of the structures represented by General Formulas (A) to (D) (where m is independently 1 or 2; a, b, c, and d are each independently a binding site to a hydrophilic group; n is 0, 1 or 2; and the wavy lines each independently mean an E-isomer or a Z-isomer).

##STR00001##

The present invention provides a liquid crystal composition and a liquid crystal display device thereof. The liquid crystal composition comprises at least one compound of general formula I and at least one compound of general formula II. The liquid crystal composition has a larger vertical dielectric constant (?.sub.?), a larger ratio of the vertical dielectric constant to the absolute value of dielectric anisotropy (?.sub.?/|??|), a larger K.sub.ave value and a higher transmittance while maintaining an appropriate clearing point, an appropriate optical anisotropy, and an appropriate absolute value of the dielectric anisotropy, such that the liquid crystal display device comprising the same has a better contrast, a faster response speed and a better transmittance while maintaining an appropriate range of operating temperature and an appropriate threshold voltage. ##STR00001##

The invention relates to a liquid-crystalline medium, having particular dielectric properties, in that it has: either a dielectric constant perpendicular to the director (.sub.) in the range of 2 or more to less 8 or less and at the same time a ratio of the dielectric constant perpendicular to the director (.sub.) to the dielectric anisotropy (), i.e. (.sub./) of 1.0 or more or or a dielectric constant perpendicular to the director (.sub.) of 8 or more and a dielectric anisotropy () of 26 or less and
preferably comprises one or more compounds having a high dielectric constant perpendicular to the director (.sub.) and a high average dielectric constant (.sub.av.). These compounds are suitable for use in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect.

The invention relates to liquid-crystalline media which can be used, in particular, for electro-optical displays having active-matrix addressing based on the ECB effect and for IPS (in-plane switching) displays or FFS (fringe field switching) displays.

Liquid-crystalline media which can be used, in particular, for electro-optical displays having active-matrix addressing based on the ECB effect and for IPS (in-plane switching) displays or FFS (fringe field switching) displays.

The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy, comprising a low-molecular-weight component and a polymerisable component. The polymerisable component comprises self-aligning, polymerisable mesogens (polymerisable 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 polymerisable self-alignment additives which have a certain position of the functional groups.

The present invention provides a liquid crystal composition comprising one or more compounds of general formula I and one or more compounds of general formula II; the liquid crystal composition of the present invention can work at very high and very low temperatures, has a very short response time and a better reliability to light and heat, and particularly exhibits no image retention or a significantly reduced image retention after a long time operation.

A liquid crystal composition includes a first compound expressed by following Chemical Formula 1 and about 0.001 wt % to about 0.05 wt % of a second compound expressed by following Chemical Formula 2, ##STR00001##
where A and B are a cyclo-hexyl group or a phenyl group, m is 0 to 4, n is 1 to 2, X is an alkyl group or an alkoxy group, and Y is one or two fluorine (F) or chlorine (Cl) atoms, and ##STR00002##
where n is 0 to 2, I is 0 to 1, Z is a halogen group, an alkyl group, or an alkoxy group, and A and A are methyl groups that do not independently exist.