45results about How to "Large negative dielectric anisotropy" patented technology

A liquid crystal composition is provided that has a wide temperature range of a nematic phase, a small viscosity, a suitable optical anisotropy, a large negative dielectric anisotropy and a large specific resistance, and a liquid crystal composition is provided that satisfies these characteristics and also has a low minimum temperature of a nematic phase, preferably −20° C. or less. A liquid crystal display device containing the liquid crystal composition is also provided. The liquid crystal composition has a negative dielectric anisotropy and contains a liquid crystal compound having an ethylene bond and 2,3-difluorophenylene as a first component and a liquid crystal compound having phenylene having halogens replacing two hydrogens as the second component, and the liquid crystal display device contains the liquid crystal composition.

A liquid crystal compound having high stability to heat, light and so forth, a high clearing point, a low minimum temperature of a liquid crystal phase, small viscosity, suitable optical anisotropy, large negative 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. The compound is represented by formula (1-1):wherein, for example, R1 is alkyl having 1 to 10 carbons, alkoxy having 1 to 9 carbons or alkenyl having 2 to 10 carbons; R2 is alkyl having 1 to 10 carbons, alkoxy having 1 to 9 carbons or alkenyl having 3 to 10 carbons; ring A1 is 1,4-cyclohexylene or 1,4-phenylene; ring A2 is 1,4-cyclohexylene, 1,4-phenylene or 2,3-difluoro-1,4-phenylene; Z1 and Z2 are single bonds; L1 and L2 are fluorine; and 1 is 0, 1 or 2.

A liquid crystal compound is to be obtained that has stability to heat, light and so forth, a high clearing point, a suitable optical anisotropy, a large negative dielectric anisotropy, and excellent compatibility with other liquid crystal compounds. A liquid crystal composition containing the compound is also to be obtained that has a low viscosity, a suitable optical anisotropy, a suitable negative dielectric anisotropy, a low threshold voltage, a high maximum temperature of a nematic phase (phase transition temperature from a nematic phase to an isotropic phase), and a low minimum temperature of a nematic phase. A compound having a hydrocoumarin skeleton is synthesized, and a liquid crystal composition containing the compound is produced.

The invention relates to a liquid crystal compound containing 2,3-difluoro-5-methyl-phenyl. The compound has a structure shown as a general formula I in the specification. The invention also relates to a preparation method of the liquid crystal compound and a composition containing the liquid crystal compound. The invention relates to an application of the liquid crystal compound and the composition in the fields of liquid crystal display. The liquid crystal compound and the composition have negative dielectric anisotropy, have a stable structure, and have good application prospect.

To provide a liquid crystal compound satisfying at least one of high stability to heat, light and so forth, a high clearing point, a 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.The compound is represented by formula (1):wherein, for example, R is alkyl having 1 to 10 carbons or alkoxy having 1 to 9 carbons; ring A1, ring A2 and ring A3 is 1,4-cyclohexylene, 1,4-phenylene or 2,3-difluoro-1,4-phenylene; at least one of L1 and L2 is fluorine and the remainder is hydrogen; Z1, Z2 and Z3 are a single bond, —(CH2)2—, —CH2O— or —COO—; x and y are an integer from 0 to 10; and l, m and n are 0 or 1.

The invention relates to a liquid crystal display element, a liquid crystal composition and a liquid crystal alignment film. The liquid crystal display element of the present invention has characteristics such as short response time, large voltage retention rate, low threshold voltage, large contrast ratio, long lifespan, and small flicker rate. The liquid crystal display element includes: an electrode group formed on one or both of a pair of oppositely arranged substrates; a plurality of active elements connected to the electrode group; a liquid crystal alignment film formed on The opposite surfaces of each of the pair of substrates; and a liquid crystal composition sandwiched between the pair of substrates, wherein the liquid crystal alignment film contains a polymer with a photodecomposable group, and the liquid crystal composition contains a group selected from the formula (1) At least one compound in the group of compounds represented by (1) is used as the first component.