| abstract |
A process for producing hollow microspheres which comprises: a step (1) in which heat-expandable microspheres having a microcapsular structure comprising a shell formed from a thermoplastic resin and, encapsulated therein, a blowing agent capable of gasifying or generating a gas and a solid material having an average particle diameter or average major-axis length smaller than the average particle diameter of the heat-expandable microspheres are dispersed in a liquid dispersion medium to prepare a slurry; and a step (2) in which the heat-expandable microspheres are heated in the slurry to soften and thermally expand the shells thereof, thereby forming hollow microspheres having the solid material adherent to the surface of the softened shells. |