Liquid crystal medium, useful in e.g. twisted nematic liquid crystal display, comprises cyclohexane compound excluding 4-butyl-4'-vinyl-bicyclohexyl, 4'-allyl-4-propyl-bicyclohexyl and 4'-((Z)-but-2-enyl)-4-propyl-bicyclohexyl

摘要

Liquid crystal medium (Q) with positive dielectric anisotropy comprises = 33 wt.% of one or more cyclohexane compound (I) excluding 4-butyl-4'-vinyl-bicyclohexyl, 4'-allyl-4-propyl-bicyclohexyl and 4'-((Z)-but-2-enyl)-4-propyl-bicyclohexyl. Liquid crystal medium (Q) with positive dielectric anisotropy comprises = 33 wt.% of one or more cyclohexane compound of formula (I) excluding 4-butyl-4'-vinyl-bicyclohexyl, 4'-allyl-4-propyl-bicyclohexyl and 4'-((Z)-but-2-enyl)-4-propyl-bicyclohexyl. R 11alkyl of formula (C iH 2i+1) or alkenyl of formula (C jH 2j-1); R 12alkenyl of formula (C kH 2k-1); either i : 1-7; and j, k : 2-7; or i+k, j+k : 6-10. An independent claim is included for the preparation of (Q) comprising mixing (I) further with fluoro substituted benzene compound of formula (II), substituted benzene compound of formula (III), substituted cyclohexane compound of formula (IV) and substituted dibenzene compound of formula (VI) (where (IV) is free of (I)), and optionally one or more additives, such that the amount of (I) in (Q) is greater than 30 wt.%. R 2, R 3optionally fluorinated 1-7C-alkyl, optionally fluorinated 1-7C-alkoxy, 2-7C-alkenyl, 2-7C-alkenyloxy, 2-7C-alkoxyalkyl or fluorinated 2-7C-alkenyl; ring A 21-A 33cyclohexan-1,4-yl, cyclohexen-1,4-yl, tetrahydro-pyran-2,5-yl, [1,3]dioxan-2,5-yl, benzen-1,4-yl, 2-fluoro-benzen-1,4-yl, or 1,3-difluoro-benzen-2,5-yl; L 21, L 22, L 31, L 32H or F; X 2, X 3halo, halogenated 1-3C-alkyl or 1-3C-alkoxy, or halogenated 2-3C-alkenyl or 2-3C-alkenyloxy; Z 3-CH 2CH 2-, -CF 2CF 2-, -COO-, trans-CH=CH-, trans-CF=CF-, -CH 2O- or a single bond; l-o : 0 or 1; R 41, R 42, R 61, R 62R 2; ring A 41, ring A 42cyclohexan-1,4-yl, cyclohexen-1,4-yl, benzen-1,4-yl, 2-fluoro-benzen-1,4-yl, 1,3-difluoro-benzen-2,5-yl, or 2,3-difluoro-benzen-1,4-yl; Z 41, Z 42, 2Z 41-CH 2CH 2-, -COO-, trans-CH=CH-, trans-CF=CF-, -CH 2O-, -CF 2O-, -C?=C- or a single bond; p, r : 0-2; ring A 6benzen-1,4-yl, 2-fluoro-benzen-1,4-yl, 1,3-difluoro-benzen-2,5-yl, or 2,3-difluoro-benzen-1,4-yl; and Z 61, Z 62-CH 2CH 2-, -COO-, trans-CH=CH-, trans-CF=CF-, -CH 2O-, -CF 2O-, or a single bond. [Image] [Image] [Image] [Image].