Polychloroprene-polyvinyl alcohol latex

In a free-radical initiated process for producing an aqueous latex having high colloidal stability against coagulation upon addition thereto of ionic materials and having excellent adhesive characteristics for bonding metal films to paper to form laminates, the step comprising polymerizing at an acidic pH in an emulsion substantially free of carboxylate soaps,

• (1) an aqueous suspension of chloroprene and an .alpha.,.beta.-unsaturated carboxylic acid having the formula ##STR3## where R is hydrogen, a C.sub.1 -C.sub.4 alkyl, or the carboxymethyl group, the mole ratio of chloroprene to the .alpha.,.beta.-unsaturated carboxylic acid being 99.6-90 to 0.4-10,
• (2) in the presence of (a) about 3-10 parts of polyvinyl alcohol and (b) about 0.3-2 parts of an organic, sulfur-containing chain transfer agent of the group consisting of dialkyl xanthogen disulfides and alkyl mercaptans, both (a) and (b) being expressed in parts by weight based on 100 parts by weight of the total of monomers (1), whereby latex is obtained of a polymer which is 10-95% gel polymer and from which the polyvinyl alcohol is not completely removable by extraction with water;
• with the proviso that an anionic, acid-stable, surface active agent may be present in the polymerization emulsion in an amount of 0.01-1% by weight, based on monomers.