Use of compounds of formula I P 1 -Sp 1 -(A 1 -Z 1) n -A 2 -Sp 4 -CH(Sp 2 -P 2)(Sp 3 -P 3) I in which the individual radicals have the following meanings: P 1, P 2, P 3 independently of each other denote a polymerisable group, Sp 1-4 independently of each other denote a spacer group or a single bond, A 1, A 2 independently of each other, and on each occurrence identically or differently, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group having 4 to 25 C atoms, which may also contain fused rings, and which is optionally mono- or polysubstituted by L, L denotes P 1-, P 1 -Sp 1 -, F, Cl, Br, I, -CN, -NO 2, -NCO, -NCS,-OCN, -SCN, -C(=O)N(R x) 2, -C(=O)Y 1, -C(=O)R x, -N(R x) 2, optionally substituted silyl, optionally substituted aryl or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25, particularly preferably 1 to 10, C atoms, in which, in addition, one or more non-adjacent CH 2 groups may each be replaced, independently of one another, by -C(R 00)=C(R 000)-, -C≡C-, -N(R 00)-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F, Cl, CN, P 1 - or P 1 -Sp 1 -, R 00 and R 000 each, independently of one another, denote H or alkyl having 1 to 12 C atoms, Y 1 is halogen, R x denotes P 1 -, P 1 -Sp 1 -, H, halogen, straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH 2 -groups are optionally replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -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 optionally replaced by F, Cl, P 1 - or P 1 -Sp 1 -, optionally substituted aryl, aryloxy, heteroaryl or Heteroaryloxy having 5 to 20 ring atoms, n is 1, 2, 3 or 4, in liquid-crystal media or LC displays. P 1, P 2, P 3 independently of each other denote a polymerisable group, Sp 1-4 independently of each other denote a spacer group or a single bond, A 1, A 2 independently of each other, and on each occurrence identically or differently, denote an aromatic, heteroaromatic, alicyclic or heterocyclic group having 4 to 25 C atoms, which may also contain fused rings, and which is optionally mono- or polysubstituted by L, L denotes P 1-, P 1 -Sp 1 -, F, Cl, Br, I, -CN, -NO 2, -NCO, -NCS,-OCN, -SCN, -C(=O)N(R x) 2, -C(=O)Y 1, -C(=O)R x, -N(R x) 2, optionally substituted silyl, optionally substituted aryl or heteroaryl having 5 to 20 ring atoms, or straight-chain or branched alkyl having 1 to 25, particularly preferably 1 to 10, C atoms, in which, in addition, one or more non-adjacent CH 2 groups may each be replaced, independently of one another, by -C(R 00)=C(R 000)-, -C≡C-, -N(R 00)-, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O- in such a way that O and/or S atoms are not linked directly to one another, and in which, in addition, one or more H atoms may be replaced by F, Cl, CN, P 1 - or P 1 -Sp 1 -, R 00 and R 000 each, independently of one another, denote H or alkyl having 1 to 12 C atoms, Y 1 is halogen, R x denotes P 1 -, P 1 -Sp 1 -, H, halogen, straight chain, branched or cyclic alkyl having 1 to 25 C atoms, wherein one or more non-adjacent CH 2 -groups are optionally replaced by -O-, -S-, -CO-, -CO-O-, -O-CO-, -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 optionally replaced by F, Cl, P 1 - or P 1 -Sp 1 -, optionally substituted aryl, aryloxy, heteroaryl or Heteroaryloxy having 5 to 20 ring atoms, n is 1, 2, 3 or 4,