US Patent 6936642 Dental materials

The invention relates to compositions containing:(a) 14 to 55 wt.-% fillers,(b) 3 to 35 wt.-% of at least one mono- or polyethylenically unsaturated compound which is not a urethane (meth)acrylate,(c) 0.1 to 5 wt.-% of at least one initiator system which is capable of starting a radical reaction,(d) 1 to 40 wt.-% plasticizers,(e) 0 to 10 wt.-% auxiliaries such as dyes, pigments, stabilizers, solvents, rheological additives such as flow-improvers and/or retarders, and(f) 30 to 81.9 wt.-% of at least two urethane (meth)acrylates with different molecular weights, these being present in a molecular weight ratio of 1.5:1 to 50:1.