Polymerisable LC material comprising one or more polymerisable mesogenic compounds and one or more compounds of formula I, (R 11 O) s Si(CH 3) 3-s -Sp 11 -NR 12 -Sp 12 -C(OR 13) t H 3-t I wherein R 11 denotes each and independently from another in each occurrence a methyl, or ethyl radical; R 12 denotes H or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more non-adjacent CH 2 groups may each be replaced, independently of one another by -CH=CH-, -C≡C-, -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 or CN; R 13 denotes each and independently from another in each occurrence a methyl, or ethyl radical, and if t denotes 2, two R 13 can form a cyclic acetal having a bridging 1,2-ethanediyl or 1,3-propanediyl; Sp 11 denotes a single bond or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more non-adjacent CH 2 groups may each be replaced, independently of one another, by -CH=CH-, -C≡C-, -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 or CN; Sp 12 denotes a single bond or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more non-adjacent CH 2 groups may each be replaced, independently from another, by -CH=CH-, -C≡C-, -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 or CN; s denotes integer from 0 to 3; and t denotes 1, 2 or 3. R 11 denotes each and independently from another in each occurrence a methyl, or ethyl radical; R 12 denotes H or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more non-adjacent CH 2 groups may each be replaced, independently of one another by -CH=CH-, -C≡C-, -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 or CN; R 13 denotes each and independently from another in each occurrence a methyl, or ethyl radical, and if t denotes 2, two R 13 can form a cyclic acetal having a bridging 1,2-ethanediyl or 1,3-propanediyl; Sp 11 denotes a single bond or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more non-adjacent CH 2 groups may each be replaced, independently of one another, by -CH=CH-, -C≡C-, -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 or CN; Sp 12 denotes a single bond or straight-chain or branched alkylene having 1 to 12 C atoms, in which one or more non-adjacent CH 2 groups may each be replaced, independently from another, by -CH=CH-, -C≡C-, -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 or CN; s denotes integer from 0 to 3; and t denotes 1, 2 or 3.