| abstract |
An object of the present invention is to provide heat-expandable microspheres excellent in heat resistance and fluidity and their use. [Solution] The thermally expandable microspheres of the present invention are composed of an outer shell made of a thermoplastic resin, a blowing agent contained therein and vaporized by heating, and the thermoplastic resin is a nitrile containing essentially acrylonitrile and methacrylonitrile Is obtained by polymerizing a polymerizable component comprising a monomer (A), a carboxyl group-containing monomer (B), a nitrile monomer (A) and a monomer (C) copolymerizable with a carboxyl group monomer, The weight ratio of the acrylonitrile is 0.1 to 9 wt%. |