Method for preparing aqueous emulsion for coating solid pharmaceutical preparations

摘要

A method for preparing an aqueous emulsion for coating solid pharmaceutical preparations comprises the steps of dissolving a cellulosic polymer in a mixed solvent of water and an organic solvent capable of being admixed with water in any rate to give a polymer solution, self-emulsifying the polymer solution by mixing with water and then concentrating the resulting emulsified stock solution. The concentration is carried out by removing a part of the liquid components while passing it through a membrane for ultrafiltration till the polymer concentration of the resulting emulsion reaches a level of not less than 7% by weight.