| 摘要 |
PROBLEM TO BE SOLVED: To obtain a liquid crystal medium which has a high resistivity and a low threshold voltage and is useful for electrooptical applications by basing upon a mixture of positively dielectrically anisotropic polar compounds containing fluorine compounds. SOLUTION: This medium contains at least one compound represented by formula I, preferably in an amount of 1-50 wt.% of the mixture. In the formula, R1 and R2 are each independently a 1-12C alkyl or alkenyl group provided that they each may be unsubstituted, monosubstituted by CN or CF3, or at least monosubstituted by halogen and that one or more CH2 groups in them may be independently substituted by -O-, -S-, -CO-, -COO-, -OCO-, or -OCOO- so that O atoms do not directly bond to each other; and u is 1 or 2. Preferably, at least one compound selected from among compounds represented by formulas II to VI, etc., is further incorporated. In these formulas, R0 is 1-9C alkyl or the like; X0 is F, Cl, a 1-6C haloalkyl, or the like; Y1 and Y2 are each H or F: Z0 is -C2H4 or the like; and r is 0 or 1. |
