Abstract: A method of coating containers made of glass, polyethylene or polyester by treatment with a substantially paraffin-free aqueous formulation comprising (A) at least one acid-functional waxy copolymer selected from (A1) partially oxidized polyethylene waxes having an acid number in the range from 10 to 100 mg KOH/g, determined in accordance with DIN 53402, with (A2) copolymers having a melt flow rate (MFR) in the range from 1 to 50 g/10 min, measured at 160° C. under a load of 325 g in accordance with EN ISO 1133, which in copolymerized form comprise (a) 60% to 88% by weight of ethylene, (b) 12% to 40% by weight of at least one ethylenically unsaturated carboxylic acid, and which are at least partially neutralized with alkali metal or amine, (B) if desired, at least one nonionic or anionic surfactant, (C) if desired, at least one defoamer, (D) if desired, at least one organic amine, (E) if desired, at least one organic solvent.