| 摘要 |
PURPOSE:To prepare a microcapsule excellent in the protection of a core substance and the fast releasability thereof, in preparing the microcapsule, by employing a specific water swellable polymer so as to be present in ethyl cellulose as a wall film of the core substance. CONSTITUTION:In preparing a microcapsule, a core substance such as a pharmaceutical substance is dispersed in a solution containing ethyl cellulose as a wall film forming agent and, after the core substance is coated with ethyl cellulose by subjecting the same to phase separation in the presence of a water swellable polymer or the water swellable polymer is compouned in the core substance to be dispersed in an ethyl cellulose containing liquid, ethyl cellulose is subjected to phase separation to coat the core substance. In this case, as the water swellable polymer, a polymer prepared by graft copolymerizing a vinyl derivative shown by a general formula[I]with water swellable polysaccharides or polyvinyl alcohol or a polymer obtained by copomerizing a vinyl derivative shown by a general formula[II]with an alkali metal salt is used. |
