| 摘要 |
PROBLEM TO BE SOLVED: To continuously manufacture spherical composite fine particles, with high degree of yields, which comprise mother particles and child particles dispersed and fixed in the mother particles and have mean particle diameter of 0.1-5.0μm, the ratio of particles having particle diameter of 1μm or less being 5% or more. SOLUTION: Mother particle raw material and child particle raw material are mixed together to prepare raw material liquid, the raw material liquid is turned into droplets through a two-fluid nozzle, and the droplets obtained are dried by means of a spray dryer or a pulse impact wave dryer. By providing such steps, composite fine particles in which mean particle diameter is 0.1-5.0μm and volume ratio of particles having diameter of 1μm or less is 5% or more are obtained. If such spherical composite fine particles are dispersed in a liquid or solid medium, high transmission of light can be obtained in a visible ray region and high shielding characteristics can be obtained in an ultraviolet ray region.
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