| 摘要 |
Hollow silica-based particles having cavities inside the outer shell having a low refractive index. The method of producing the silica-based particles comprises the following steps (a) and (b): (a) a step in which, when an aqueous silicate solution and/or an acidic silicic acid solution and an aqueous solution of an alkali-soluble inorganic compound are simultaneously added in an alkali aqueous solution to prepare a dispersion liquid of composite oxide particles, an electrolytic salt is added at the molar ratio of a mole number of the electrolytic salt (M<SUB>E</SUB>) versus that of SiO<SUB>2 </SUB>(M<SUB>S</SUB>) [(M<SUB>E</SUB>)/(M<SUB>S</SUB>)] in the range from 0.1 to 10, and (b) a step of furthermore adding an electrolytic salt, if necessary, to the dispersion liquid of composite oxide particles and then removing at least a portion of elements constituting the composite oxide other than silicon by adding an acid to prepare a dispersion liquid of silica-based particles. |
