| 摘要 |
#CMT# #/CMT# Liquid crystalline medium (A) comprises at least one difluoro-dibenzofuran compound (I). #CMT# : #/CMT# Liquid crystalline medium (A), based on a mixture of polar compounds, comprises at least one dibenzofuran compound of formula (I). R 11>, R 12>H, 1-15C alkyl or alkenyl (optionally substituted by CN, CF 3 or halo), where the CH 2 group is substituted by -cyclobutane- -Ctriple boundC, -CF 2O-, -OCF 2-, -OC-O- or -O-CO- and the O atoms are not linked directly with one another; and ring A : 1,4-cyclohexenyl or 1,4-cyclohexyl (where one or two non-adjacent CH 2 group is replaced by -O or -S), 1,4-phenyl, where one or two CH-group is replaced by N, piperidin-1,4-diyl, 1,4 bicyclo[2,2,2]-octyl, naphthalen-2,6-diyl, decahydronaphthalen-2,6-diyl, 1,2,3,4-tetrahydronaphthalen-2,6-diyl, phenanthrene-2,7-diyl, fluorene-2,7-diyl, where all the residues are substituted one or more times by halo. Independent claims are included for: (1) the preparation of (A) comprising mixing one or more compound of (I) with at least a further liquid crystalline compound and optionally adding additives; and (2) an electro optical display with an activematrix-addressing based on a vertical aligned-, electrically controlled birefringence-, PALC-, fringe field switching- or in plane switching effect, comprising (I) as a dielectric. #CMT#[Image]#/CMT# #CMT#USE : #/CMT# As a liquid crystal composition in electro optical displays (claimed). #CMT#ADVANTAGE : #/CMT# The polar compound exhibits rotation viscosity, high dielectric anisotropy and long-term stability. #CMT#ORGANIC CHEMISTRY : #/CMT# Preferred Composition: (A) further comprises one or more: aromatic-fluoro compound of formula (IIA) or (IIB) and a cyclohexane compound of formula (III). (A) contains 1-4 or more compounds of (I). The amount of (I), (IIA) and/or (IIB) and (III) is at least 2-20 (preferably 2), 20-80 (preferably 20) and 3 wt.%, respectively. The total amount of (I) and (IIA) and/or (IIB) is less than or equal to 100. R 2>0-15C alkyl or alkenyl (optionally substituted by CN, CF 3 or halo), where in these residue one or more CH 2 group is substituted by -O-, -S-, -cyclobutane-, -C=?C, -CO-, -CO-O, - O-CO or -O-CO-O and the O atoms are not connected directly; R 31>, R 32>alkyl, alkenyl, alkoxyalkyl or 0-12C alkoxy; A1 : -phenyl-, -cyclohexane-, -cyclohexene- compound of formula (a) or (b) or pyran compound of formula (c) or (d); Z : single bond, -CH 2CH 2-, -CH=CH-, -CF 2O-, -OCF 2-, -CH 2O-, -OCH 2-, -COO-, -OCO, -C 2F 4 or -CF=CF; p : 1-2; and v : 1-6. #CMT#[Image]#/CMT# #CMT#[Image]#/CMT# #CMT#[Image]#/CMT# #CMT#DEFINITIONS : #/CMT# Preferred Definitions: ring A : e.g. cyclohexane, tetrahydropyran, dioxane, benzene, difluoro-benzene or fluoro-benzene; and R 11>1-6C alkyl. |
