42results about How to "Lower limit temperature" patented technology

Provided is a liquid crystal compound, which has large dielectric anisotropy, a high voltage retention rate and good stability in the presence of light and heat, becomes a nematic phase within a broad temperature range, has the appropriate optical anisotropy, and has excellent compatibility with other liquid crystal compounds, particularly a liquid crystal compound having large dielectric anisotropy. The compound is represented by formula (1) (1) where, for instance, R1 is a C1-20 alkyl, rings A1, A2, A3, A4, A5 and A6 are, independently, 1,4-cyclohexylene or 1,4-phenylene; Z1, Z2, Z3, Z4, Z5, Z6 and Z7 are, independently, single bonds, -(CH2)2-, -COO-, -OCO-, -CF2O-, -OCF2-, or -CH=CH-; X1 is a fluorine, -CF3, or -OCF3; and Y1 and Y2 are, independently, hydrogen or fluorine.

Provided are: a liquid crystal compound satisfying at least one physical property such as high stability with respect to heat, light, and the like, high clearing point, low lower-limit temperature in the liquid crystal phase, low viscosity, suitable optical anisotropy, large dielectric constant anisotropy, suitable elastic constants, and exceptional compatibility with other liquid crystal compounds; a liquid crystal composition containing this compound; and a liquid crystal display element including this composition. A compound represented by formula (1). In formula (1), for example, R1 is a C1-C15 alkyl; ring A1 and ring A2 are 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, 1,4-phenylene having at least one hydrogen substituted by a halogen, tetrahydropyran-2,5-diyl, or 1,3-dioxan-2,5-diyl; Z1 and Z2 are a single bond or -CF2O-; L1, L2, and L3 are halogen or hydrogen; and a is 0-3.

The present invention provides a liquid-crystal display element having properties such as a wide temperature range where the element is usable, a short response time, a high voltage holding ratio, a low threshold voltage, a high contrast ratio, and a long life. The liquid-crystal display element of the present invention comprises a first substrate, a plurality of pixel electrodes formed on the first substrate, a second substrate, counter electrodes formed on the second substrate and facing the pixel electrodes, a liquid-crystal layer present between the pixel electrodes and the counter electrodes and comprising a liquid-crystal composition, and alignment control layers constituted of a polymer comprising an aligning monomer, which was a component of the liquid-crystal composition, and formed respectively on the first-substrate side and the second substrate side. The aligning monomer is a polymerizable polar compound comprising both a mesogen moiety constituted of at least one ring anda polar group. Due to this, the alignment control layers in the liquid-crystal display element of the present invention can perpendicularly align the liquid-crystal compound contained in the liquid-crystal composition, without the necessity of forming an alignment film.

A compound represented by formula (1). For example, R1 represents an alkyl group having 1-15 carbon atoms; MES represents a mesogenic group having at least one ring; Sp1 represents a single bond or analkylene group having 1-10 carbon atoms; M1 represents a methyl group; and each of R2, M2 and M3 represents a hydrogen atom.(img file='DDA0001544777320000011. TIF'wi='830' he='270' / )

Disclosed is a liquid crystal composition that satisfies at least one property of a high upper limit temperature of a nematic phase, a low lower limit temperature of a nematic phase, a low viscosity, a proper optical anisotropy, a negatively large permittivity anisotropy, a large specific resistance, a high stability against ultraviolet light, a high stability against heat and the like, or has a proper balance between at least two of the above properties. Also disclosed is an AM element possessing a short response time, a large voltage retention, a large contrast ratio, and a long service life and the like. The liquid crystal composition that comprises a specific fluorine substituted tetracyclic compound having a high upper limit temperature as a first component and a specific compound having a negatively large permittivity anisotropy as a second component and has a negative permittivity anisotropy. Further disclosed is a liquid crystal display element comprising the composition.

The present invention addresses the problem of providing: a polymerizable compound having suitable polymerization reactivity, a high conversion rate, a low polymerization initiation temperature, and ahigh solubility in a liquid crystal composition; a liquid crystal composition containing said compound; and a liquid crystal display device containing said composition. To resolve the problem, a compound represented by formula (1), and a liquid crystal composition containing said compound are provided. In formula (1), R<1>, R<2>, and R<3> are each independently an alkyl, etc.; n is 0, etc.; ringA<1> is phenyl, etc.; ring A<2> and ring A<3> are each independently 1,4-phenylene, etc.; Z<1> and Z<2> are each independently a single bond, etc.; Sp<1>-Sp<4> are single bonds, etc.; a is 1, etc.; c,d, and e are each independently 0 or 1; the sum of c, d, and e is 1, etc.; P<1>-P<4> are polymerizable groups; and at least one among P<1>-P<4> is a polymerizable group represented by formula (P-1).

Since a switching element using a nematic liquid crystal medium has a long response time, there is a limit to the number of control instances over a certain time. By using a liquid crystal compositionexhibiting an optical isotropic phase, an element capable of performing polarization control at high speed is provided. A mixture comprising the liquid crystal composition and polymerizable monomers,a polymer / liquid crystal composite material obtained by polymerizing the mixture, an element comprising the liquid crystal composition or the polymer / liquid crystal composite, and a LIDAR comprisingthe element are provided.

The invention provides a polymeric compound and its polymer, a liquid crystal composition and a liquid crystal display element. A polymerizable compound having suitable polymerization reactivity, high conversion rate and good solubility in liquid crystal composition is provided. Provides high upper limit temperature of nematic phase, low lower limit temperature of nematic phase, small viscosity, suitable optical anisotropy, large dielectric constant anisotropy, suitable elastic constant, large specific resistance , and a liquid crystal composition having physical properties such as suitable pretilt. To provide liquid crystal display elements with wide temperature range, short response time, high voltage retention, low threshold voltage, high contrast, suitable pretilt and long life. A compound represented by formula (1), a liquid crystal composition, and a liquid crystal display element.