Method for producing disintegrated silica particles

Silica particles calcined in a calcination step are supplied in a swirling flow generated by a gas introduced in a disintegration container and disintegrated therein, whereby the silica particles can be easily disintegrated and there can be obtained disintegrated silica particles having both low hygroscopicity and high dispersibility in resin. In addition, the introduction of dehumidified air (gas) during the disintegration reduces hygroscopicity and greatly improves dispersibility in resin. Furthermore, performing heating treatment (calcination) again after the disintegration causes the surface modification of the disintegrated silica particles, greatly improving hygroscopicity and dispersibility in resin. The resin composition obtained in this manner including silica particles provides good injectability and filterability when used for an underfill material for semiconductors and an in-plane spacer or sealing spacer of liquid crystal displays.