摘要 |
Provided is a process for efficiently producing heat-expandable microspheres having high solvent resistance. The process produces the heat-expandable microspheres composed of a shell of a thermoplastic resin and a blowing agent encapsulated therein and vaporizable by heating, and includes the steps of preparing an aqueous suspension by dispersing an oily mixture containing a polymerizable component, the blowing agent, and a polymerization initiator containing, as an essential component, a peroxide A having a theoretical active oxygen content of at least 7.8%, and polymerizing the polymerizable component in the oily mixture. |