Composition comprising at least one compound of the formula where the symbols and indices used are as follows: X is the same or different at each instance and is O, S or NR 0; Y is the same or different at each instance and is O or S; X 1 is O or S; a is 0 or 1; Sp is an alkanediyl, alkenediyl or an alkynediyl, which may be substituted by one or more R groups; R 0 is a straight-chain or branched alkyl group having 1 to 10 carbon atoms; R 1, R 2, R 3 and R 4 are each independently at each instance H, F, Cl, Br, I, a straight-chain or branched alkyl group having 1 to 20 carbon atoms, a partly or fully halogenated straight-chain or branched alkyl group having 1 to 20 carbon atoms or an aryl or heteroaryl group having 5 to 40 ring atoms; R 5, R 6, R 7, R 8 and R 9 are each independently at each instance H, F, Cl, Br, I, a straight-chain or branched alkyl group having 1 to 20 carbon atoms, a straight-chain or branched alkoxy group having 1 to 20 carbon atoms, a partly or fully halogenated straight-chain or branched alkyl group having 1 to 20 carbon atoms, a partly or fully halogenated straight-chain or branched alkoxy group having 1 to 20 carbon atoms or an aryl or heteroaryl group having 5 to 40 ring atoms, where at least one radical from the group of substituents R 5 to R 9 is a straight-chain or branched alkyl group having 1 to 20 carbon atoms that may be partly or fully halogenated; R 10, R 11, R 12 are each independently at each instance H, F, a linear or branched alkyl group which has 1 to 20 carbon atoms and may be partly or fully halogenated, or an aryl group having 6 to 14 carbon atoms; R is the same or different at each instance and is selected from the group consisting of a straight-chain or branched alkyl group having 1 to 10 carbon atoms, a partly halogenated or fully halogenated straight-chain or branched alkyl group having 1 to 10 carbon atoms, a straight-chain or branched alkoxy group having 1 to 10 carbon atoms or a partly halogenated or fully halogenated straight-chain or branched alkoxy group having 1 to 10 carbon atoms; at least one hydrophilic monomer selected from 3-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, glyceryl methacrylate, glyceryl acrylate, acrylamide, N-vinylpyrrolidone, 6-hydroxyhexyl methacrylate, 6-hydroxyhexyl acrylate, 18-hydroxyoctadecyl methacrylate, 18-hydroxyoctadecyl acrylate, 11-hydroxyundecyl methacrylate, 11-hydroxyundecyl acrylate, 12-hydroxydodecyl methacrylate, 12-hydroxydodecyl acrylate, ethylene glycol phenyl ether acrylate, ethylene glycol phenyl ether methacrylate or a combination of these compounds; at least one UV absorber and at least one crosslinker, where the molar ratio of the sum total of all compounds of the formula to the sum total of all hydrophilic monomers is 1:0.51 to 1:1.24. X is the same or different at each instance and is O, S or NR 0; Y is the same or different at each instance and is O or S; X 1 is O or S; a is 0 or 1; Sp is an alkanediyl, alkenediyl or an alkynediyl, which may be substituted by one or more R groups; R 0 is a straight-chain or branched alkyl group having 1 to 10 carbon atoms; R 1, R 2, R 3 and R 4 are each independently at each instance H, F, Cl, Br, I, a straight-chain or branched alkyl group having 1 to 20 carbon atoms, a partly or fully halogenated straight-chain or branched alkyl group having 1 to 20 carbon atoms or an aryl or heteroaryl group having 5 to 40 ring atoms; R 5, R 6, R 7, R 8 and R 9 are each independently at each instance H, F, Cl, Br, I, a straight-chain or branched alkyl group having 1 to 20 carbon atoms, a straight-chain or branched alkoxy group having 1 to 20 carbon atoms, a partly or fully halogenated straight-chain or branched alkyl group having 1 to 20 carbon atoms, a partly or fully halogenated straight-chain or branched alkoxy group having 1 to 20 carbon atoms or an aryl or heteroaryl group having 5 to 40 ring atoms, where at least one radical from the group of substituents R 5 to R 9 is a straight-chain or branched alkyl group having 1 to 20 carbon atoms that may be partly or fully halogenated; R 10, R 11, R 12 are each independently at each instance H, F, a linear or branched alkyl group which has 1 to 20 carbon atoms and may be partly or fully halogenated, or an aryl group having 6 to 14 carbon atoms; R is the same or different at each instance and is selected from the group consisting of a straight-chain or branched alkyl group having 1 to 10 carbon atoms, a partly halogenated or fully halogenated straight-chain or branched alkyl group having 1 to 10 carbon atoms, a straight-chain or branched alkoxy group having 1 to 10 carbon atoms or a partly halogenated or fully halogenated straight-chain or branched alkoxy group having 1 to 10 carbon atoms;