Modelling material which contains (a) at least one radically polymerizable monomer, (b) at least one initiator for the radical polymerization and (c) at least one inert component. The inert component (c) is selected from phthalates, polyethylene glycols (PEG), polypropylene glycols (PPG), PEG-PPG copolymers, glycerol derivatives, ethoxylated or propoxylated glycerol, ethylenediamine tetrakispropoxylates and ethylenediamine tetrakisethoxylates. The material is suitable in particular for the production of models of dental restorations for investment casting processes.