Patent ID: 7553523

Claim:
A liquid crystal medium comprising 1-30% by weight of one or more compounds of formula IA, 1-10% by weight of one or more compounds of formula IB, 0-9% by weight of one or more compounds of formula IC, wherein R 1 and R 2 are each, independently of one another, an alkyl radical having 1 to 12 carbon atoms which is unsubstituted, monosubstituted by CF 3 or at least monosubstituted by halogen, wherein one or more CH 2 groups are optionally, in each case independently of one another, 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, Y 1 is H or F, X is F, Cl or a halogenated alkyl, alkenyl, alkoxy or alkenyloxy radical having up to 6 carbon atoms, and r is 1 or 2, and wherein the medium has a birefringence at 20° C. that is lower than 0.08, and wherein the medium does not contain a compound comprising a cyano group.