Can coatings from nitrile copolymer latexes

The process consisting of coating at least one side of a metal sheet, said metal being selected from the group consisting of steel, tin-plated steel and aluminum, with a layer of a polymer latex maintained at a pH of from 4.5 to 6.7, drying said layer and heating the thus-coated sheet for a short time at a temperature in the range of from 200.degree. to 300.degree. C. wherein the polymer is prepared by polymerization in aqueous emulsion of 100 parts by weight of

• (A) from 60 to 90% by weight of at least one nitrile having the structure ##STR9## wherein R is hydrogen, a lower alkyl group having from 1 to 4 carbon atoms, or a halogen, and
• (B) from 10 to 40% by weight based on the combined weight of (A) and (B) of at least one member selected from the group consisting of
• (1) an ester having the structure ##STR10## wherein R.sub.1 is hydrogen, an alkyl group having from 1 to 4 carbon atoms, or a halogen, and R.sub.2 is an alkyl group having from 1 to 6 carbon atoms,
• (2) an alpha-olefin having the structure ##STR11## wherein R' and R" are alkyl groups having from 1 to 7 carbon atoms, (3) a vinyl ether selected from the group consisting of methyl vinyl ether, ethyl vinyl ether, the propyl vinyl ethers, and the butyl vinyl ethers,
• (4) vinyl acetate, and
• (5) styrene,
• in the presence of from 0 to 40 parts by weight of
• (C) a rubbery polymer of a conjugated diene monomer selected from the group consisting of butadiene and isoprene and a comonomer selected from the group consisting of styrene, a monomer having the structure ##STR12## wherein R has the foregoing designation, and an ester having the structure ##STR13## wherein R.sub.1 and R.sub.2 have the foregoing respective designations, said rubbery polymer containing from 50 to 100% by weight of polymerized conjugated diene and from 0 to 50% by weight of comonomer.