It is preferred that the acrylic material be a monomer or oligomer. [0053] Suitable as the acrylic component are, for example, the diacrylates of cycloaliphatic or aromatic diols, such as 1,4-dihydroxymethylcyclohexane, 2,2-bis(4-hydroxycyclohexyl)propane, 1,4-cyclohexanedimethanol, bis(4-hydroxycyclohexyl)meth