A liquid-crystalline medium having a nematic phase containing one or more compounds of formula D

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the use thereof in an electro-optical display, particularly in an active-matrix display based on the IPS or FFS effect, displays of this type which contain a liquid-crystalline medium of this type and the use of the compounds of formula D for improvement of the contrast and/or response times of a liquid-crystalline medium which contain one or more additional mesogenic compounds, as well as certain compounds of formula D.

The invention relates to a liquid-crystalline medium, preferably having a nematic phase and dielectric anisotropy of 0.5 or more, which comprises one or more compounds of formula Y ##STR00001##
in which the parameters have the meanings 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 Y for the improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.

Disclosed is a polymerizable liquid crystal material wherein an amount of a salt represented by the following formula (I) is less than 0.01 parts by mass per 100 parts by mass of a polymerizable liquid crystal compound, and an amount of a nitrogen-containing compound represented by the following formula (II) is 0.01 parts by mass or less per 100 parts by mass of the polymerizable liquid crystal compound. 10 to R.sup.5 each independently represent a hydrogen atom or a C1-C7 alkyl group, R.sup.6 and R.sup.7 represents a hydrogen atom, and X represents F.sup., Br.sup., Cl.sup., I.sup., HSO.sub.4.sup., 1/2(HPO.sub.4.sup.2), H.sub.2PO.sub.4.sup., RC(O)O.sup., 1/2(.sup.O(CO)R(CO)O.sup.) or RSO.sub.3.sup., where R represents a hydrogen atom or a monovalent hydrocarbon group, and R represents a single bond or a divalent hydrocarbon group.

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To provide a liquid crystal display device that has a high off-response speed and a good balance between drive voltage and transmittance, is stable over time, and also has a high voltage holding ratio. A liquid crystal display device in which a liquid crystal layer containing a polymer network (A) and a liquid crystal composition (B) is disposed between two substrates having an electrode on at least one side thereof and having transparent properties on at least one side thereof, and the loss factor (tan ) (loss modulus/storage modulus) of the liquid crystal layer calculated from the storage modulus (Pa) and the loss modulus (Pa) in a sinusoidal vibration measured with a rheometer at 25 C. and at a measurement frequency of 1 Hz ranges from 0.1 to 1.

The invention relates to a liquid-crystalline medium, in particular based on a mixture of polar compounds, and to the use thereof for an active-matrix display, in particular based on the VA, SA-VA, IPS, PS-IPS, FFS, PS-FFS, UB-FFS or PS-UB-FFS effect.

Provided are a liquid crystal composition satisfying at least one of characteristics such as high maximum temperature, low minimum temperature, small viscosity, suitable optical anisotropy, large negative dielectric anisotropy, large specific resistance, high stability to ultraviolet light and high stability to heat, or has a suitable balance regarding at least two of the characteristics; and an AM device having characteristics such as a short response time, a large voltage holding ratio, low threshold voltage, a large contrast ratio and a long service life. The liquid crystal composition may contain a specific compound having large negative dielectric anisotropy as a first component, a specific compound having high maximum temperature as a second component, a specific compound having negative dielectric anisotropy as a third component, or a specific compound having a polymerizable group as an additive component.

The present invention relates to a mixture comprising a not fully aromatic polymerisabe compound and a polymerisable photoinitiator, to liquid-crystal (LC) media comprising them, and to the use of the polymerisable compounds and LC media for optical, electro-optical and electronic purposes, in particular in LC displays, especially in LC displays of the polymer sustained alignment type.

Disclosed is a compound containing a specific structure having an azomethine part, the compound being reversibly fluidized and non-fluidized by being irradiated with light.

Provided are liquid crystal compounds and mixtures incorporating the same. The liquid crystal compounds of the invention generally comprise a cyclopentane group and at least two other rings. In one embodiment, the liquid crystal compounds of the invention comprise a cyclopentane group and at least two other rings, one of which is a fused ring system.

The present disclosure relates to a liquid crystal composition, and a liquid crystal display element or liquid crystal display comprising the liquid crystal composition, and belongs to the field of liquid crystal display, said liquid crystal composition comprises a compound represented by formula I, a compound represented by formula II, one or more compounds represented by formula III, and at least one polymerizable compound, wherein the liquid crystal composition simultaneously has a low rotary viscosity, a large refractive index, and a fast response speed.

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