| abstract |
Liquid-crystalline medium based on a mixture of polar compounds with positive dielectric anisotropy, characterized in that it contains one or more compounds of the formula I contains wherein R 1 is alkyl or alkoxy having 1 to 15 C atoms and R 2 alkenyl with 2 to 7 carbon atoms means and one or more compounds of formula IVb contains wherein R 0 is alkyl, alkoxy, fluoroalkyl, alkenyl or oxaalkenyl having up to 9 C atoms and X 0 F, Cl, CF 3 , OCF 3 , OCHF 2 , fluoroalkyl or fluoroalkoxy having up to 7 carbon atoms means. |