Liquid crystal composition and its liquid crystal display device

Abstract

The present invention provides a liquid crystal composition, which comprises: at least one compound of general formula I; at least one compound of general formula II-1 and / or general formula II-2; at least one compound of general formula a compound of M; and at least one compound of formula N. The present invention also provides a liquid crystal display device comprising the liquid crystal composition. The liquid crystal composition provided by the present invention has suitably high optical anisotropy, suitably high clearing point, good low-temperature stability, high dielectric anisotropy, high transmittance, and large elastic constant, When the liquid crystal composition is applied to an IPS liquid crystal display device, the transmittance of the display device can be effectively improved, so that the display device has good energy saving and environmental protection characteristics while having a good display effect.

Description

technical field [0001] The invention relates to the field of liquid crystal materials, in particular to a liquid crystal composition and a liquid crystal display device thereof. Background technique [0002] Liquid Crystal Display (LCD) has been developed rapidly due to its small size, light weight, low power consumption and excellent display quality, and is especially widely used in portable electronic information products. With the increase in the size of LCD screens for portable computers, office applications, and video applications, there are still some problems to be solved in order to enable LCD displays to be used for large-screen display and eventually replace cathode ray tubes (Cathode Ray Tube, CRT). Such as improving viewing angle characteristics, increasing response speed, increasing contrast, increasing transmittance, etc. The relatively narrow viewing angle of the LCD means that when viewed away from the direction perpendicular to the normal line of the liquid...

AI Technical Summary

Problems solved by technology

They all have their own advantages and disadvantages: MVA mode has the characteristics of high contrast and fast response, but it needs a biaxial compensation film and two elliptical polarizers, so the cost is higher; OCB mode is difficult to maintain stable control with AC voltage , the transmittance of R, G, and B monochromatic light is also different. In addition, in the case of no field, the molecules in the liquid crystal cell are arranged in a direction parallel to the substrate. In order to achieve a curved arrangement, it is necessary to Add a voltage to the box for a few seconds to preset, and then maintain this arrangement at a lower voltage, which is inconvenient to use; IPS mode only needs a linear polarizer without a compensation film, but its response speed is too fast Slow, unable to display fast-moving pictures

[0015] In addition, in order to maintain a sufficiently high transmittance, the absolute value of the dielectric anisotropy of most liquid crystal compositions in the prior art is relatively low, resulting in a relatively high driving voltage of a liquid crystal display device comprising such a liquid crystal composition, The direct result is that the energy-saving and environmental protection performance of liquid crystal display devices is affected

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