abstract |
A polymer composed of 15 to 75% by weight of a nitrile monomer, 10 to 65% by weight of a carboxyl group, 0.1 to 20% by weight of a monomer having an amide group, and 0.1 to 20% by weight of a monomer having a cyclic structure in its side chain is used. A thermally expandable microcapsule containing a foaming agent. |