Patent ID: 7041347

Claim:
A liquid-crystalline medium, comprising two or more liquid crystal compounds wherein at least one compound is of formula I wherein R a is an alkenyl group having from 2 to 9 carbon atoms, R b is alkenyl with 2 to 9 carbon atoms, L is, in each occurrence independently, F, Cl, CN or an optionally mono- or polyhalogenated alkyl, alkoxy, alkenyl or alkenyloxy group having up to 3 carbon atoms, and r is 0, 1, 2, 3 or 4; and said mixture further comprises at least one compound of the formula in which A is 1,4-phenylene or trans-1,4-cyclohexylene, a is 0 or 1, R 3 is an alkenyl group having from 2 to 9 carbon atoms, and R 4 is an alkyl group having 1 to 12 carbon atoms which is unsubstituted, monosubstituted by CN or CF 3 or at least monosubstituted by halogen, and wherein one or more CH 2 groups are each, independently of one another, optionally replaced by —O—, —S—, —CH═CH—, —C≡C—, —CO—, —CO—O—, —O—CO— or —O—CO—O— in such a way that O atoms are not linked directly to one another.