. . "Examples of the monomers which are suitable in principle as aliphatically unsaturated monomers (b) include vinyl compounds, for example vinyl ketones, such as vinyl ethyl ketone and vinyl n-butyl ketone, vinyl esters, such as vinyl acetate and vinyl propionate; allyl compounds; (meth)acrylic compounds, such as (meth)acrylic esters, for example methyl acrylate, methyl methacrylate, n-butyl acrylate" . .