Patent ID: 7923079

Claim:
A liquid-crystalline medium of positive dielectric anisotropy based on a mixture of compounds comprising: one or more compounds of the formula I in which R 1 denotes a halogenated or unsubstituted alkyl or alkoxy radical having 1 to 15 C atoms, where, in addition, one or more CH 2 groups in these radicals are each, independently of one another, replaced by —C≡C—, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, ring A denotes a ring system of the formulae pointing to the left or right, Z 1 , Z 2 denote a single bond, —C≡C—, —CF═CF—, —CH═CH—, —CF 2 O— or —CH 2 CH 2 —, where at least one group from Z 1 and Z 2 denotes the group —CF═CF—, X denotes F, Cl, CN, SF 5 or a halogenated or unsubstituted alkyl or alkoxy radical having 1 to 15 C atoms, where, in addition, one or more CH 2 groups in these radicals are each, independently of one another, replaced by —C≡C—, —CH═CH—, —O—, —CO—O— or —O—CO— in such a way that O atoms are not linked directly to one another, L 1 , L 2 , L 3 , L 4 , L 5 and L 6 each, independently of one another, denote H or F, and m 1; and one or more compounds of formulae XIV and XV: in which R 0 is in each case independently n-alkyl having up to 9 C atoms, oxaalkyl having up to 9 C atoms, fluoroalkyl having up to 9 C atoms, or alkenyl having up to 9 C atoms, X 0 is F, Cl, halogenated alkyl having up to 6 C atoms, halogenated alkenyl having up to 6 C atoms, halogenated alkenyloxy having up to 6 C atoms, or halogenated alkoxy having up to 6 C atoms, and rings B and C, independently of one another, are each 1,4-phenylene which is substituted by 0, 1 or 2 fluorine, wherein at least one of the 1,4-phenylene rings is mono- or polysubstituted by fluorine; and further comprising one or more compounds of formulae Z-1 to Z-9 and/or one or more compounds of formulae II, III, IV, V and VI wherein R 1a and R 2a each, independently of one another, denote H, CH 3 , C 2 H 5 or n-C 3 H 7 , R 0 denotes n-alkyl having up to 9 C atoms, oxaalkyl having up to 9 C atoms, fluoroalkyl having up to 9 C atoms, or alkenyl having up to 9 C atoms, alkyl, alkyl* denote an unsubstituted n-alkyl radical having 1 to 7 C atoms, alkenyl denotes an unsubstituted alkenyl radical having 2-7 C atoms, X 0 denotes F, Cl, halogenated alkyl having up to 9 C atoms, halogenated alkenyl having up to 9 C atoms, halogenated alkenyloxy having up to 9 C atoms, or halogenated alkoxy having up to 6 C atoms, Z 0 denotes —C 2 F 4 —, —CF═CF—, —C 2 H 4 —, —(CH 2 ) 4 —, —OCH 2 —, —CH 2 O—, —CF 2 O— or —OCF 2 —, Y 1 to Y 4 each, independently of one another, denote H or F, r denotes 0 or 1, and t denotes 0, 1 or 2.