Method of using aqueous polymer dispersions as lamination adhesives for glossy films

A process for laminating a glossy polymer film to a paper or cardboard substrate-which comprises:

• (1) applying to said glossy polymer film an aqueous polymer dispersion based on acrylate-methacrylate copolymers, said dispersion having a solids content of from 20 to 65% by weight, the copolymer having a glass transition temperature of from -35.degree. to -10.degree. C., a Fikentscher K value of from 40 to 100 and a mean particle size of less than 200 nm, and the copolymer is obtainable by free-radical emulsion polymerization of a comonomer phase containing:
• a) from 50 to 80 parts by weight of one or more comonomers from the group consisting of alkyl acrylates of alcohols having 2 to 10 carbon atoms,
• b) from 10 to 25 parts by weight of one or more comonomers from the group consisting of alkyl methacrylates of alcohols having 1 to 10 carbon atoms,
• c1) from 0.5 to 10 parts by weight of styrene,
• c2) from 0.1 to 4.0 parts by weight of one or more .alpha., .beta.-unsaturated, monoolefinic carboxylic acids,
• c3) from 0 to 4.0 parts by weight of one or more .alpha., .beta.-unsaturated, monoolefinic carboxamides,
• c4) from 0 to 8 parts by weight of one or more comonomers selected from the group consisting of hydroxyalkyl acrylates and hydroxylalkyl methacrylates made from esters of acrylic acid or methacrylic acid and diols having 2 to 10 carbon atoms, and
• c5) from 0.1 to 4.0 parts by weight of one or more comonomers selected from the group consisting of acrylamido-propane sulfonic acid, vinylsulfonic acid, styrene sulfonic acid and the salts thereof,
• (2) allowing said aqueous dispersion to dry,
• (3) applying the thus obtained coated polymer film to said substrate with the coat in contact with said substrate, and
• (4) laminating said glossy polymer film to said substrate by heat-sealing at an elevated temperature and under pressure.