Liquid-crystalline medium

A liquid-crystalline medium based on a mixture of polar compounds of negative dielectric anisotropy, which comprises at least one compound of the formula I1 and/or I2

• at least one compound of the formula I3
• in which
• R11, R2 and R3 are each, independently of one another, an unsubstituted alkyl or alkenyl radical having 1 to 12 carbon atoms, in which one or more non-adjacent CH2 groups are optionally replaced by a radical selected from the group consisting of —O—, —S— and —C≡C—,
• R12 is CsH2s+1, —O—C(CH3)═CH2 or —O—(CH2)bCH═CH2
• Q is —O— or a single bond,
• Z is C2H4—, —CH═CH— or a single bond,
• s, t, and u are each, independently of one another, from 1 to 6,
• o and p are each, independently of one another, 1 or 2 and
• b is 0, 1, 2, or 3;
• and additionally comprises at least one compound selected from those of the formulae IIIa or IIIb
• wherein Alkyl and Alkyl* are each, independently of one another, straight-chain alkyl having 1-6 carbon atoms;
• and
• additionally comprises one or more compounds of the formulae IA and/or IB
• in which
• R7 and R8 are each, independently of one another, as defined for R11 and R2 and,
• w and x are each, independently of one another, from 1 to 6.

A liquid-crystalline medium which consists essentially of:

• 10-30% by weight of one or more compounds of the formulae I1 and/or I2,
• 30-70% by weight of one or more compounds of the formula I3, and
• 5-50% by weight of one or more compounds of the formula II
• in which
• R11, R2 and R3 are each, independently of one another, an unsubstituted alkyl or alkenyl radical having 1 to 12 carbon atoms, in which one or more non-adjacent CH2 groups are optionally replaced by a radical selected from the group consisting of —O—, —S— and —C≡C—,
• R12 is CsH2s+1, —O—C(CH3)═CH2 or —O—(CH2)bCH═CH2
• Q is —O— or a single bond,
• Z is —C2H4—, —CH═CH— or a single bond,
• s, t, and u are each, independently of one another, from 1 to 6,
• o and p are each, independently of one another, 1 or 2,
• b is 0, 1, 2, or 3
• R4 is as defined for R11 and R2, and
• v is from 1 to 6.