| abstract |
PURPOSE: To provide inorganic fine spheres having a uniform particle diameter by adding the aqueous solution of an inorganic compound capable of forming precipitates with a metal salt to a W/O type emulsion, the W/O type emulsion being prepared by pressing the aqueous solution of a metal salt into an organic solvent through a micro porous member. n CONSTITUTION: The aqueous solution of an alkali metal silicate, carbonate, phosphate or sulfate, an alkaline earth metal halide or a copper or iron sulfate, chloride or nitrate, etc., is pressed into an organic solvent containing a surfactant through a micro porous member subjected to a hydrophobic treatment with a silane coupling agent, etc., to form a W/O type emulsion. The aqueous solution of an inorganic compound capable of forming precipitates with the above-mentioned metal salt is added to the emulsion, and the produced precipitates are filtered, separated and dried to provide inorganic uniform fine spheres useful as a sustained release inorganic microcapsule wall material. n COPYRIGHT: (C)1992,JPO&Japio |