There is provided a liquid crystal composition which enables a significant reduction in crystallization temperature as compared with addition of a homolog while having a similar skeleton structure, which has an excellent compatibility, and which enables an increase in the absolute value of negative dielectric anisotropy (Δ∈). The liquid crystal composition contains two or more compounds which each have two to four ring structures between two side chains. At least one of the ring structures is a 2,3-difluorobenzene skeleton. The two side chains are bonded to different ring structures. The positions of the 2,3-difluorobenzene skeletons are different from each other, and the number of the ring structures are the same as each other.

There is provided a liquid crystal composition containing any one or two or more of compounds represented by general formula (i) below and any one or two or more of compounds represented by general formula (ii) below. ##STR00001##

The present invention relates to the technical field of liquid crystal displays, and particularly relates to a liquid crystal composition containing a 2-methyl-3,4,5-trifluorobenzene liquid crystal compound and use thereof, wherein the liquid crystal composition of the present invention comprises, in percentages by weight, 1-50% of one or more compounds represented by general formula I and 10-70% of one or more compounds represented by general formula II, and may further comprise 0-30% of compounds represented by general formula III and/or 6-45% of one or more compounds represented by general formulas IV to XIII The liquid crystal composition provided by the present invention has a low rotational viscosity and a large elastic constant, is presented as having a shorter response time, and can significantly improve the display effect of a liquid crystal display when applied to TN, IPS and FFS mode displays.

A liquid-crystalline medium having a nematic phase, a dielectric anisotropy of 0.5 or more and a ratio of the dielectric constant perpendicular to the director (∈.sub.⊥) to the dielectric anisotropy (Δ∈), i.e. (∈.sub.⊥/Δ∈), of 2.0 or less and comprises one or more compounds of formula I

##STR00001##

wherein the parameters have the meaning given in the text.

An electro-optical display containing such a medium, particularly in an active-matrix display based on the IPS or FFS effect. Methods for using of the compounds of formula I for improvement of the transmission and/or response times of a liquid-crystalline medium which comprises one or more additional mesogenic compounds.

A liquid-crystalline medium, in particular based on a mixture of polar compounds, having compounds of formulae Y, CY, PY and/or LY, and compounds of formula S1 and/or S2:

##STR00001##

It is an object of the present invention to provide a liquid crystal composition having positive Δ∈, having a liquid crystal phase in a wide temperature range, having high solubility at low temperatures, having high ODF process compatibility, having a high specific resistance and voltage holding ratio, and being insensitive to heat and light. In order to achieve this object, there is provided a liquid crystal composition containing at least one compound represented by the following general formula (i) and at least one compound represented by the following general formula (ii). ##STR00001## (wherein R.sup.i1 denotes an alkyl group having 2 to 5 carbon atoms) ##STR00002## (wherein R.sup.ii1 and R.sup.ii2 independently denote an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and X.sup.ii1 and X.sup.ii2 independently denote a hydrogen atom or a fluorine atom)

There is provided a liquid crystal composition that exhibits a sufficiently low viscosity (η), a sufficiently low rotational viscosity (γ1), and a large elastic modulus (K.sub.33) without decreasing the refractive index anisotropy (Δn) and the nematic phase-isotropic liquid phase transition temperature (T.sub.ni) and without increasing the solid phase-nematic phase transition temperature (T.sub.cn). The liquid crystal display element that uses this liquid crystal composition satisfactorily obtains a pretilt angle and has a high voltage holding ratio (VHR) and high-speed response. Thus, a liquid crystal display element that has no or less alignment defects and display defects such as image sticking, and has high display quality and high response speed is obtained.

A liquid crystal composition containing a benzochromene compound and the use thereof in a liquid crystal display element or liquid crystal display. The liquid crystal composition comprises one or more compounds represented by Formula I and one or more compounds represented by Formula II. The liquid crystal composition has the characteristics of a small rotational viscosity, a large elastic constant, a high transmittance, a fast response speed, a strong resistance to ultraviolet light irradiation, and a high long-time light stability, and is particularly suitable for the field of TV display.

##STR00001##

As a material used in an element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz, a liquid crystal composition is required, which has a high upper limit temperature of a nematic phase, a low lower limit temperature of a nematic phase, large dielectric anisotropy and a small tan δ in a frequency region where the phase control of an electromagnetic wave signal is performed, and stability against heat, and which has an excellent balance of the characteristics. A liquid crystal composition which is used in an element for phase control of an electromagnetic wave signal having any frequency from 1 GHz to 10 THz, the liquid crystal composition containing at least one compound selected from compounds represented by Formula (1) as a first component. ##STR00001##

The present invention provides a novel liquid crystal material composition comprising one or more compound, in order to achieve the properties of low viscosity, high resistivity, good low-temperature mutual solubility, fast response, excellent transmission, and which can be used for a variety of fast response display modes. Since the working temperature of a LCD material is subjected to the temperature range of individual LC molecules, information can only be displayed in a specific temperature range of the specific liquid crystal macro-alignment phase. At low temperature, the viscosity of liquid crystal increases exponentially, which in turn substantially reduces the response speed and overall performances of the display system. The liquid crystal composition according to the present invention overcomes these problems with balanced chemical composition by achieving low viscosity, good low-temperature performance and excellent transmission in a wide range of LCD applications including TN, IPS or FFS displays, thus improving display performance.