Superimposed prosthetic racing material

A denture base separating material comprising an aqueous emulsion obtained by emulsion polymerization of methacrylic ester, acrylic ester, or acrylonitrile alone, or a mixed solution of two or more thereof, in the presence of a water-soluble radical polymerization initiator and a surfactant, the monomer composition of which is adjusted such that the minimum film-forming temperature is 23 DEG C or lower has an appropriate adhesion and is able to be readily removed from the tissue conditioner. The emulsion polymerization may be carried out in the presence of up to 7 parts, by weight of polymer, of a phthalic ester or a fatty acid ester, or such an ester may be added to the polymer emulsion.