The present invention provides a process for converting a solid (meth)acrylate copolymer into a dispersed form by preparing an aqueous dispersion comprising the components (a) a (meth)acrylate copolymer which is composed of free-radical polymerized methyl methacrylate, ethylacrylate and a salt of 2-trimethylammoniumethyl methacrylate, present in solid form as a powder or as a granulate, (b) up to 50% by weight calculated on the (meth)acrylate copolymer (a) of a dispersing agent selected from the groups of (b) i) plasticizers in combination with emulsifiers and/or (b) ii) pharmaceutically acceptable carbohydrates having 6 to 18 carbon atoms with a functional group and (c) water by mixing the components (a), (b) and (c) to give a suspension which becomes an aqueous dispersion during the conversion of the solid (meth)acrylate copolymer into the dispersed form, characterized in that, the (meth)acrylate copolymer is converted into the dispersed form by means of the presence of the dispersing agent at a temperature of less than 50° C.