PURPOSE: To make it possible to improve the water resistance and adhesion of a film prepared from the obtained latex, by polymerizing a (meth)acrylate- based monomer mixture in the presence of a specified seed latex.

CONSTITUTION: The polymerization is performed according to the following first and second stages. First stage: a monomer mixture comprising 0.5W50wt% carboxyl group-containing ethylenically unsaturated monomer (a), 20W99.5wt% (meth)acrylate (b), 0W79.5wt% other ethylenically unsaturated monomers (c) is emulsion-polymerized in an aqueous medium containing 0.5W7pts.wt., per 100pts.wt. monomer mixture, nonionic and/or anionic surfactants to obtain a seed latex. Second stage: a monomer mixture comprising 20W100wt% (meth) acrylate (d), 0W7wt% carboxyl group-containing ethylenically unsaturated monomer (e) and 0W80wt% other ethylenically unsaturated monomers (f) is allowed to flow into the system and polymerized in the presence of the seed latex.