The liquid crystal display device includes a pair of substrates consisting of first and second substrates arranged to face each other, a liquid crystal layer sandwiched between the first and second substrates, a pixel electrode disposed on at least one of the first and second substrates, a common electrode disposed on at least one of the first and second substrates, a light source section including a light-emitting element, and a photoconversion layer including pixels of three primary colors consisting of red (R), green (G), and blue (B). The photoconversion layer contains a light-emitting nanocrystal having an emission spectrum of any of red (R), green (G), and blue (B) upon receiving light emitted from the light source section on at least one of the three primary colors. The liquid crystal layer contains a liquid crystal composition containing a compound represented by General Formula (i) at 10% to 50% by mass.

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.

The invention relates to a liquid crystal compound having the structure of formula I wherein R is selected from the group consisting of H and alkyl or alkoxy groups of 1 to 12 carbon atoms in which one or more H are unsubstituted or substituted with halogen; A.sub.1 is selected from the group consisting of a single bond or a 1,4-phenylene group in which each H in the 1,4-phenylene group is independently substituted by one or more halogen atoms; L.sub.1 and L.sub.2 are each independently selected from H or halogen; Z.sub.1 is a single bond or (CH.sub.2).sub.2. The compound has advantages of low rotational viscosity, large dielectric anisotropy, good mutual solubility and stability, which can be added to LC composition to reduce the driving voltage of the display. Thus, the novel compound has prosperous applications in LCD industry. ##STR00001##

A liquid crystal compound having positive dielectric anisotropy is provided and contains a compound represented by formula (1) as a first component, a compound represented by formula (2) as a second component, a polar compound as a first additive and a polymerizable compound as a second additive. ##STR00001## In formula (1), R.sup.1a is alkyl having 1 to 12 carbons, or the like; ring Q and ring S are independently 1,4-cyclohexylene, 1,4-phenylene or the like; Z.sup.1a and Z.sup.2a are independently a single bond or the like; X.sup.1a and X.sup.2a are independently hydrogen or fluorine; Y.sup.1a is fluorine, chlorine, alkyl having 1 to 12 carbons in which at least one hydrogen is replaced by fluorine or chlorine, or the like; q is 1, 2, 3 or 4; s is 0, 1, 2 or 3; and a sum of q and s is 4 or less.

A liquid crystal compound having positive dielectric anisotropy is provided and contains a compound represented by formula (1) as a first component, a compound represented by formula (2) as a second component, a polar compound as a first additive and a polymerizable compound as a second additive. ##STR00001## In formula (1), R.sup.1a is alkyl having 1 to 12 carbons, or the like; ring Q and ring S are independently 1,4-cyclohexylene, 1,4-phenylene or the like; Z.sup.1a and Z.sup.2a are independently a single bond or the like; X.sup.1a and X.sup.2a are independently hydrogen or fluorine; Y.sup.1a is fluorine, chlorine, alkyl having 1 to 12 carbons in which at least one hydrogen is replaced by fluorine or chlorine, or the like; q is 1, 2, 3 or 4; s is 0, 1, 2 or 3; and a sum of q and s is 4 or less.

The present invention discloses a liquid crystal composition comprising at least one compound of general formula I and a display device thereof. The present invention also discloses a liquid crystal display device comprising the liquid crystal composition of the present invention. The liquid crystal composition provided by the present invention has characteristics, such as a high absolute value of negative dielectric anisotropy, a high optical anisotropy, a superior low-temperature stability, a fast response speed and so forth. The liquid crystal display device comprising the liquid crystal composition of the present invention can satisfy the demand for low driving voltage and fast response.

##STR00001##

The invention relates to a liquid-crystalline medium comprising at least one compound of the formula I, ##STR00001## in which R.sup.1 and R.sup.2 have the meanings indicated in Claim 1, and to the use thereof in electro-optical liquid-crystal displays.

The invention relates to a liquid-crystalline medium comprising at least one compound of the formula I, ##STR00001## in which R.sup.1 and R.sup.2 have the meanings indicated in Claim 1, and to the use thereof in electro-optical liquid-crystal displays.

A liquid crystal composition comprises a compound of general formula I serving as a first component; a compound of general formula II-1 and/or general formula II-2 serving as a second component; a compound of general formula III serving as a third component; a compound of general formula IV serving as a fourth component; a compound of general formula V serving as a fifth component; and a compound of general formula VI serving as a sixth component. The liquid crystal composition has at least one characteristic among the characteristics of a large dielectric anisotropy, a large optical anisotropy, a high voltage holding ratio and a low threshold voltage and the like, and is suitable to be used in a liquid crystal display device. Additionally, a liquid crystal display device comprising the liquid crystal composition is also provided.

Mesogenic media comprising one or more compounds of formulae I or II ##STR00001##
preferably mesogenic media showing a blue phase, preferably stabilized by a polymer, and their use in electro-optical light modulation elements and their respective use in displays, as well as such devices.