Hydroxy group containing diesters of acrylic acids and their use in dental material

A monomeric binding agent in dental material, especially in dental filling material, comprising between 30 and 80% by weight of a finely divided filler and a diacrylate prepared by reacting 3-(3,4-epoxycyclohexyl)-8,9-epoxy-2,4-dioxaspiro (5,5) undecane or a bis-epoxide of formula (A) ##STR7## or a bis-epoxide of formula (B) ##STR8## with a hydroxyalkylacrylate or hydroxyalkylmethacrylate containing 2 to 10 carbon atoms in the alkyl portion, n being 0 to 1 in formula (A) with the proviso that if

• n is 0, X is -0- and R.sup.1 is -H;
• and that if
• n is 1, X is selected from the group of alkylene with 1 to 10 carbon atoms, C.sub.1-3 -alkyl substituted alkylene with 1 to 10 carbon atoms, -0-(CH.sub.2).sub.m -0-where m is 1 to 10, -CH.sub.2 -OCO-(CH.sub.2).sub.p -COO-CH.sub.2 where p is 1 to 6, and -CH.sub.2 -OCO-, and R.sup.1 is -H or -CH.sub.3,
• and in formula (B) ##STR9## or tricyclo-[5,2,1,0.sup.2,6 ]-decylene.