abstract |
The invention relates to a process for producing mouldings by injection moulding the steps in the process being a) melting and mixing of a (meth)acrylate copolymer composed of from 85 to 98% by weight of C1-C4-alkyl (meth)acrylates capable of free-radical polymerization and from 15 to 2% by weight of (meth)acrylate monomers having a quaternary ammonium group in the alkyl radical, with from 10 to 25% by weight of a plasticizer, and also from 10 to 50% by weight of a dryers [sic] and/or from 0.1 to 3% by weight of a release agent, and, where appropriate, with other conventional pharmaceutical additives or auxiliaries and/or with an active pharmaceutical ingredient, b) devolatilizing the mixture at temperatures of at least 120° C., thus reducing the content of the low-boiling constituents with a vapour pressure of at least 1.9 bar at 120° C. to not more than 0.5% by weight, and c) injecting the devolatilized mixture at a temperature of from 80 to 160° C. into the mould of an injection moulding system and removing the resultant moulding from the mould. |