Liquid crystal medium comprising one or more polymerisable compounds of formula I below, and further comprising one or more mesogenic or liquid crystalline compounds comprising an alkenyl group, in which the individual radicals have the following meanings m is 0 or 1, P 1, P 2, P 3 independently of each other denote a polymerisable group, Sp 1, Sp 2, Sp 3 independently of each other denote a spacer group or a single bond, wherein at least one of Sp 1, Sp 2 and Sp 3 is different from a single bond, L denotes P-Sp-, 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 or P-Sp-, R 00 and R 000 each, independently of one another, denote H or alkyl having 1 to 12 C atoms, r is 0, 1, 2 or 3, R x denotes P-Sp-, 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 or P-Sp-, optionally substituted aryl, aryloxy, heteroaryl or heteroaryloxy having 5 to 20 ring atoms, P has one of the meanings given for P 1, Sp has one of the meanings given for Sp 1 or Sp 2. wherein the following mixtures are disclaimed: Mixtures obtained by adding 3.5% of the compound of the formula I-2a-1 to the nematic host mixture H3, H4, H6 or H8, and adding to the resulting mixture 0.3% of the compound RM34. H3: Nematic host-mixture CC-3-V1 9.00 % Clearing point [°C]: 74.7 CCH-23 18.00 % Δn [589 nm, 20°C]: 0.098 CCH-34 3.00 % Δε [1 kHz. 20°C]: -3.4 CCH-35 7.00 % ε ∥ [1 kHz, 20°C]: 3.5 CCP-3-1 5.50 % ε ⊥ [1 kHz, 20°C]: 6.9 CCY-3-02 11.50 % K 1 [pN, 20°C]: 14.9 CPY-2-02 8.00 % K 3 [pN, 20°C]: 15.9 CPY-3-02 11.00 % γ1 [mPa·s, 20°C]: 108 CY-3-02 15.50 % V 0 [20°C, V]: 2.28 PY-3-02 11.50 % H4: Nematic host-mixture CC-3-V 37.50 % Clearing point [°C]: 74.8 CC-3-V1 2.00 % Δn [589 nm, 20°C]: 0.099 CCY-4-O2 14.50 % Δε [1 kHz. 20°C]: -2.9 CPY-2-O2 10.50 % ε ∥ [1 kHz, 20°C]: 3.7 CPY-3-O2 9.50 % ε ⊥ [1 kHz, 20°C]: 6.6 CY-3-O2 15.00 % K 1 [pN, 20°C]: 12.2 CY-3-O4 4.50 % K 3 [pN, 20°C]: 13.4 PYP-2-4 5.50 % γ 1 [mPa·s, 20°C]: 92 PPGU-3-F 1.00% V 0 [20°C, V]: 2.28 H6: Nematic host-mixture CC-4-V 17.00 % Clearing point [°C]: 106.1 CCP-V-1 15.00 % Δn [589 nm, 20°C]: 0.120 CCPC-33 2.50 % Δε [1 kHz, 20°C]: -3.6 CCY-3-O2 4.00 % ε ∥ [1 kHz, 20°C]: 3.5 CCY-3-O3 5.00 % ε ⊥ [1 kHz, 20°C]: 7.0 CCY-4-O2 5.00 % K 1 [pN, 20°C]: 16.8 CLY-3-O2 3.50 % K 3 [pN, 20°C]: 17.3 CLY-3-O3 2.00 % γ 1 [mPa·s, 20°C]: 207 CPY-2-O2 8.00 % V 0 [20°C, V]: 2.33 CPY-3-O2 10.00 % CY-3-O4 17.00 % PYP-2-3 11.00 % H8: Nematic host-mixture CY-3-O2 15.00 % Clearing point [°C]: 74.7 CY-5-O2 6.50 % Δn [589 nm, 20°C]: 0.108 CCY-3-O2 11.00 % Δε [1 kHz, 20°C]: -3.0 CPY-2-O2 5.50 % ε ∥ [1 kHz, 20°C]: 3.6 CPY-3-O2 10.50 % ε ⊥ [1 kHz, 20°C]: 6.6 CC-3-V 28.50 % K 1 [pN, 20°C]: 12.9 CC-3-V1 10.00 % K 3 [pN, 20°C]: 15.7 PYP-2-3 12.50 % γ 1 [mPa·s, 20°C]: 97 PPGU-3-F 0.50 % V 0 [20°C, \/]: 2.42 m is 0 or 1, P 1, P 2, P 3 independently of each other denote a polymerisable group, Sp 1, Sp 2, Sp 3 independently of each other denote a spacer group or a single bond, wherein at least one of Sp 1, Sp 2 and Sp 3 is different from a single bond, L denotes P-Sp-, 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 or P-Sp-, R 00 and R 000 each, independently of one another, denote H or alkyl having 1 to 12 C atoms, r is 0, 1, 2 or 3, R x denotes P-Sp-, 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 or P-Sp-, optionally substituted aryl, aryloxy, heteroaryl or heteroaryloxy having 5 to 20 ring atoms, P has one of the meanings given for P 1, Sp has one of the meanings given for Sp 1 or Sp 2. Mixtures obtained by adding 3.5% of the compound of the formula I-2a-1 to the nematic host mixture H3, H4, H6 or H8, and adding to the resulting mixture 0.3% of the compound RM34.