COMPOUND HAVING BRANCHED ALKYL OR BRANCHED ALKENYL, OPTICALLY ISOTROPIC LIQUID CRYSTAL MEDIUM AND OPTICAL ELEMENT
申请人:JNC Corporation
公开号:EP2586764A1
公开(公告)日:2013-05-01
The first object of the invention is to provide a liquid crystal compound that is stable to heat, light and so on, and has a large optical anisotropy, a large dielectric anisotropy and a low melting point. The second object is to provide a liquid crystal medium that is stable to heat, light and so on, has a broad temperature range of a liquid crystal phase, a large optical anisotropy and a large dielectric anisotropy, and exhibits an optically isotropic liquid crystal phase. The third object is to provide a variety of optical elements containing the liquid crystal medium, which can be used in a broad temperature range and has a short response time, a high contrast and a low driving voltage.
A liquid crystal compound with branched alkyl or branched alkenyl as represented by formula (1), a liquid crystal medium (a liquid crystal composition or a polymer/liquid crystal composite material) containing the liquid crystal compound, and an optical element containing the liquid crystal medium are described.
In formula (1), R1 is branched alkyl of C3-20 or branched alkenyl of C3-20. The ring A1, A2, A3, A4 or A5 is 1,4-phenylene or 1,3-dioxane-2,5-diyl, for example. Z1, Z2, Z3 and Z4 are independently a single bond or C1-4 alkylene, for example. Y1 is fluorine, for example, m, n and p are independently 0 or 1, and 1≤m+n+p≤3.
本发明的第一个目的是提供一种液晶化合物,它对热、光等都很稳定,具有较大的光学各向异性、较大的介电各向异性和较低的熔点。第二个目的是提供一种液晶介质,该介质对热、光等稳定,具有宽温度范围的液晶相、大的光学各向异性和大的介电各向异性,并呈现光学各向同性液晶相。第三个目的是提供含有该液晶介质的各种光学元件,它可在宽温度范围内使用,响应时间短,对比度高,驱动电压低。
本发明描述了由式(1)表示的具有支链烷基或支链烯基的液晶化合物、含有该液晶化合物的液晶介质(液晶组合物或聚合物/液晶复合材料)以及含有该液晶介质的光学元件。
在式 (1) 中,R1 是 C3-20 的支链烷基或 C3-20 的支链烯基。环 A1、A2、A3、A4 或 A5 是 1,4-亚苯基或 1,3-二氧六环-2,5-二基。Z1、Z2、Z3 和 Z4 独立地为单键或 C1-4 亚烷基等。Y1是氟,例如,m、n和p独立地为0或1,且1≤m+n+p≤3。