| 摘要 |
Disclosed is a ferroelectric liquid crystal mixture containing one or more phenanthridine derivatives of formula (I), wherein E<1>, E<2> are the same or different and represent -N-, -CF- or -CH-; R<1>, R<2> are the same or different, for example a straight-chain or branched alkyl radical with 1-20 carbon atoms; Q is -CH2-O-, -CO-O or a single bond; M<1>, M<2> are the same or different and represent -CO-O-, -O-CO-, -CH2-O-, -O-CH2, -CH2-CH2-, -CC- or a simple bond; A<1>, A<2> are the same or different and represent 1,4-phenylene, where one or more H atoms can be replaced by F, trans-1,4-cyclohexylene, pyrimidine-2,5-diyl, pyridine-2,5-diyl, where one H atom can be replaced by F, (1,3,4)-thiadiazol-2,5-diyl, 1,3-dioxan-2,5-diyl, 1,3-dithian-2,5-diyl, 1,3-thiazol-2,4-diyl, 1,3-thiazol-2,5-diyl, thiopehn-2,4-diyl or thiophen-2,5-diyl; m, n are zero or one, but add up to no more than one. The addition of small amounts of phenanthridine derivatives of formula (I) is sufficient to produce ferroelectric liquid crystal mixtures with high negative values for dielectric anistropy. |
