摘要 |
Liquid crystal mixtures having positive anisotropy of the dielectric constants which comprise a nematogenic mixture with a clearing point above 60 DEG C. which is doped with an organic solvent or solvent mixture with a specific resistance of at least 107 Ohm.cm. as well as a dipole moment along the longitudinal axis of the molecule of less than 3.5 Debye, or with a compound of the formula <IMAGE> (a) wherein R14 and R15 are straight-chain alkyl containing a total of not more than 14 carbon atoms or R14 is straight-chain alkyl and R15 is straight-chain alkoxy containing a total of not more than 8 carbon atoms, or a compound of the formula <IMAGE> (b) wherein R16 and R17 are straight-chain alkyl containing a total of not more than 6 carbon atoms, or a compound of the formula <IMAGE> (c) wherein R16 and R17 are straight-chain alkyl containing a total of not more than 6 carbon atoms, or mixtures thereof, are described. |