Non-vitreous ceramic metal oxide microcapsules

Abstract From the Canadian patent

Shaped and fired porous or impermeable non-, vitreous ceramic microcapsules of metal oxide preferably, transparent and polycrystalline are made by a non-melt, process comprising the liquid-liquid extraction of aqueous metal oxide precursor with a dehydrating liquid having a limited water solubility, and drying and firing the resulting gelled microcapsules. For example, and aqueous titania sol is added to an agitated body of n-butanol to form a dispersion of droplets of said sol and water is rapidly extracted from the droplets to form gelled microcapsules; the latter are recovered by filtration dried, and fired, to convert them into transparent sealed or heat-sealable, non-vitreous ceramic …