| 摘要 |
PROBLEM TO BE SOLVED: To provide readily flowable powdery film coating compositions with good redispersibility in water, which are suitable for pharmaceutical dosage forms, and which do not change in the release behavior even in an extended or thermally severe storage.SOLUTION: The invention relates to a method for producing powdery coating compositions from an aqueous polymer dispersion, the dispersion comprising a polymer, obtained by radical polymerization between a) as component A, N,N-diethylaminoethyl methacrylate, and b) as component B, at least one radically polymerizable compound, selected from among esters of α,β-ethylenically unsaturated monocarboxylic and dicarboxylic acids and C-C-alkanols, the method being characterized in that the aqueous polymer dispersion is transferred into a powder by a spray method in the presence of a drying gas, wherein the input temperature of the drying gas into the spray device is at least 20°C above the glass transition temperature of the polymer and at least 20°C above the minimum film formation temperature of the polymer, and the output temperature of the drying gas from the spray device is maintained at 40-85°C.SELECTED DRAWING: None |
