The present invention relates to liquid-crystalline media (LC media) having negative or positive dielectric anisotropy comprising self-alignment additives (SAMs) with an at least one bifunctional or polyfunctional anchor group, which effects the 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 liquid-crystalline medium (LC medium) without conventional imide alignment layers. The LC media may be supplemented by a polymerizable or polymerized component, which serves for stabilization of the alignment, for adjustment of the tilt angle and/or as passivation layer.

The invention relates to a liquid-crystalline medium having a nematic phase comprising one or more compounds of formula X

##STR00001##

wherein the parameters have the meaning given in the text, to the use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, to displays of this type which contain a liquid-crystalline medium of this type and to the use of the compounds of formula X for improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds, as well as to the compounds of formula X.

The present invention relates to a liquid crystal display that incorporates a particular liquid crystal composition and a sealant in which a cured form of a particular curable resin composition is used. The present invention provides a liquid crystal display that prevents reduced voltage holding ratio (VHR) and increased ionic density (ID) in the liquid crystal layer and solves the problems of display defects such as voids, alignment irregularities, and image-sticking. Liquid crystal displays according to the present invention, featuring the ability to prevent reduced voltage holding ratio (VHR) in the liquid crystal layer and reduce the occurrence of display defects such as alignment irregularities and image-sticking, are useful particularly to liquid crystal displays in the IPS and FFS modes for active matrix drive and applicable to liquid crystal displays of equipment such as liquid crystal TVs, monitors, mobile phones, and smartphones.

This invention provides an FFS type liquid crystal display containing one type or two or more types of compounds selected from the group of compounds represented by General Formula (i), General Formula (ii), and General Formula (iii) and one type or two or more types of compounds selected from compounds represented by General Formula (II). This display makes it possible to realize excellent display characteristics without deteriorating various liquid crystal display characteristics such as dielectric anisotropy, viscosity, nematic-phase maximum temperature, nematic-phase stability at low temperatures, or γ.sub.1 and the display burn-in characteristics.

The present invention relates to a liquid crystal display device including a pair of a substrate arranged opposite to each other, an electrode group disposed on one side or both sides of the pair of substrates facing each other, a plurality of active devices connected to the electrode group, a liquid crystal alignment film disposed on each facing side of the pair of substrates, and a liquid crystal layer interposed between the pair of substrates, wherein the liquid crystal alignment film is manufactured by irradiating linearly polarized light to a film obtained from polyamic acid or a derivative thereof having a photoisomerization structure in the main chain or a film being subject to heat-baking so as to provide alignment-controlling capability, and the liquid crystal layer is a liquid crystal composition having negative (−) dielectric anisotropy. By the present invention, a liquid crystal display device having improved image sticking characteristics and good alignment stability is provided.

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.

An object of the present invention is to provide a liquid crystal display element using a liquid crystal composition having negative dielectric anisotropy, which is capable of realizing excellent display properties by being used in an FFS mode liquid crystal display element without deteriorating various properties, as a liquid crystal display element, such as dielectric anisotropy, viscosity, a nematic phase upper limit temperature, nematic phase stability at low temperature, and γ.sub.1, and burn-in characteristics of the display element.

Provided is an FFS mode liquid crystal display element using an n-type liquid crystal composition so as to achieve the above object.

There is provided a liquid crystal composition having the following properties without suffering reductions in refractive index anisotropy (Δn) and nematic phase-isotropic liquid phase transition temperature (T.sub.m): sufficiently low viscosity (η), sufficiently low rotational viscosity (γ1), a large elastic constant (K.sub.33), and a negative dielectric anisotropy (Δ∈) with a large absolute value. There is also provided a liquid crystal display device of, for example, a VA type that uses such a liquid crystal composition and that has a high response speed and excellent display quality with defective display being eliminated or reduced. In particular, a liquid crystal composition having a negative dielectric anisotropy is provided, the composition containing a first component that is at least one compound represented by General Formula (i) and a second component that is at least one compound selected from compounds represented by General Formula (L).