Nematic phase liquid crystal composition

Abstract

The invention discloses a nematic phase liquid crystal composition comprising a compound with a first component shown as the general formula I, a compound with a second component shown as the general formula II, a compound with a third component shown as the general formula III, a compound with a fourth component shown as the general formula IV and a compound with a fifth component shown as the general formula V. The nematic phase liquid crystal composition disclosed by the invention has very low overall response time, lower voltage, high resistivity and voltage retention rate, low viscosity, short response time and proper optical anisotropy and dielectric anisotropy; after being treated at high temperature, the nematic phase liquid crystal composition still has high resistivity and excellent high temperature and ultraviolet stability, can be used for a photoelectric display with an active matrix address, and is particularly suitable for manufacturing active matrix TN-TFT (Twisted Nematic Thin Film Transistor) and IPS-TFT (In-Plane Switching Thin Film Transistor) liquid crystal display elements and liquid crystal displays which are rapid in response.

Description

technical field [0001] The invention relates to a liquid crystal display material, in particular to a dielectric positive nematic liquid crystal composition. Background technique [0002] LCD display modes include TN (twist nematic, twisted nematic) mode, STN (super twisted nematic, super twisted nematic) mode, ECB (electrically controlled birefringence, electrically controlled birefringence) mode, OCB (optically compensated bend, optically compensated bending ) mode, IPS (in-plane switching, coplanar transformation) mode, VA (vertical alignment, vertical alignment) mode, etc. Regardless of the display mode, the liquid crystal material used has the characteristics of low driving voltage, high response speed, wide operating temperature range, large absolute value of dielectric anisotropy, high phase transition temperature and low viscosity. [0003] In the early 1990s, a new liquid crystal display mode appeared, that is, TFT (Thin Film Transistor, thin film transistor array ...

AI Technical Summary

Problems solved by technology

However, TFT-LCD displays require that the liquid crystal materials used must have good thermal, chemical, electrical, and light stability, high charge retention, low viscosity, and resistivity (ρ≥1.0×10 13 Ω·cm), these properties are unsatisfactory for traditional cyano- and ester-containing compounds

Although biphenyl and phenylcyclohexane liquid crystals containing cyano groups have high dielectric anisotropy and good electro-optic properties, studies have shown that compounds containing terminal cyano groups are easy to introduce ionic impurities, and the voltage maintains Low rate; ester liquid crystal has the characteristics of simple synthesis method, wide variety, and wide phase transition range, but its high viscosity makes it less used in TFT-LCD formulations

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