Liquid-crystalline medium

A liquid-crystalline medium comprising a self-alignment additive for vertical alignment, and at least one polymerizable compound of formula I or a polymer comprising the at least one polymerizable compound in polymerized form,

• P-Sp-(A2-Z2-A1)m1-Z1-T I
• wherein the individual radicals, independently of each other, and on each occurrence identically or differently, have the following meanings
• T is a group selected from the following formulae
• Rg is H or straight chain or branched alkyl or alkoxyalkyl with up to 10 C atoms, or benzyl,
• Ra,b,c,d are each independently straight chain or branched alkyl with 1 to 10 C atoms,
• P is vinyloxy, acrylate, methacrylate, fluoroacrylate, chloroacrylate, oxetane or epoxy,
• Sp is a spacer group or a single bond,
• A1, A2 are each independently an alicyclic, heterocyclic, aromatic or heteroaromatic group with 4 to 30 ring atoms, which may also contain fused rings, and is optionally substituted by one or more groups L or R-(A3-Z3)m2—, and one of A1 and A2 may also denote a single bond,
• A3 is an alicyclic, heterocyclic, aromatic or heteroaromatic group with 4 to 30 ring atoms, which may also contain fused rings, and is optionally substituted by one or more groups L,
• Z1 is —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CF2O—, —OCF2—, —CF2S—, —SCF2—, —(CH2)n—, —CF2CH2—, —CH2CF2—, —(CF2)n—, —CH═CH—, —CF═CF—, —CH═CF—, —CF═CH—, —C≡C—, —CH—CH—CO—O—, —O—CO—CH—CH—, —CH2—CH2—CO—O—, —O—CO—CH2—CH2—, —CR00R000—, or a single bond, with the proviso that, if m1 is 0 and Sp is a single bond, Z1 is a single bond,
• Z2, Z3 are each independently —O—, —S—, —CO—, —CO—O—, —O—CO—, —O—CO—O—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CF2O—, —OCF2—, —CF2S—, —SCF2—, —(CH2)n—, —CF2CH2—, —CH2CF2—, —(CF2)n—, —CH═CH—, —CF═CF—, —CH═CF—, —CF═CH—, —C≡C—, —CH═CH—CO—O—, —O—CO—CH═CH—, —CH2—CH2—CO—O—, —O—CO—CH2—CH2—, —CR00R000—, or a single bond,
• R00, R000 are each independently H or alkyl having 1 to 12 C atoms,
• R is P-Sp-, H, F, Cl, CN, or straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH2-groups are optionally replaced by —O—, —S—, —CO—, —CO—O—, —O—CO—, or —O—CO—O in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl or P-Sp-, or R is a group selected from formula 1, 2, 3 and 4,
• L in each occurrence is independently P-Sp-, F, Cl, CN, or straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH2-groups are optionally replaced by —O—, —S—, —CO—, —CO—O—, —O—CO—, or —O—CO—O— in such a manner that O- and/or S-atoms are not directly connected with each other, and wherein one or more H atoms are each optionally replaced by F, Cl or P-Sp-, or L is a group selected from formula 1, 2, and 3,
• m1 is 0, 1, 2, 3 or 4,
• m2 is 0, 1, 2, 3 or 4, and
• n is 1, 2, 3 or 4.