| 摘要 |
PURPOSE:To obtain the title monodisperse inorg. globular particulates with controllable diameters and narrow particle-size distribution by forming a W/O type sol emulsion from the sol contg. a specified metal oxide and gelling the sol in the emulsion. CONSTITUTION:(a) A metal oxide sol alone or the metal oxide-contg. sol obtained by incorporating the inorg. compd. of other elements, alkoxides, or sol into the above-mentioned metal oxide sol is violently mixed with an org. solvent insoluble in water or difficulty soluble in water in the presence of a surfactant to prepare a W/O type sol emulsion. (b) A basic substance or an electrolyte is added to gel sol forming a water layer in the W/O type sol emulsion, and a spherical hydrogel is obtained. (c) The obtained spherical gel emulsion is heated to remove water from the gel by azotropic dehydration and contracted, the org. solvent is then removed, dried it, and the fine bead powder is obtained. (d) The fine bead powder is calcined, and the desired fine oxide bead powder is obtained.
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