Abstract: A water based coating composition which has excellent shelf stability and can be cured by ordinary baking in the absence of a sulfonic acid-containing acid catalyst and which gives a coating having excellent adhesion and excellent water resistance. The water based coating composition can be obtained by dissolving or dispersing50 to 80% by weight, as a solid content, of a water-soluble polyester resin prepared by polycondensing a carboxylic acid component containing 10 to 60 mol % of a polycarboxylic acid having 3 to 4 carboxyl groups per molecule and 40 to 90 mol % of a dicarboxylic acid and 1.1 to 2.0 mol, per mole of the carboxylic acid component, of a glycol component, to obtain a polyester resin having a free carboxyl group, and dissolving the polyester resin in water in the presence of a base,5 to 20% by weight, as a solid content, of a water based bisphenol type epoxy resin, and15 to 45% by weight, as a solid content of an alkyl-etherified amino resin, in an aqueous medium.

Abstract: A water based coating composition which gives a coating being capable of withstanding heat treatment of food for sterilization, particularly, retorting treatment, having sufficiently high hardness against scratching in transferring and transportation, having processability sufficient to withstand the formation of cans having a variety of forms, and having little organic solvent content. The above water based coating composition contains, as resin components, 20 to 80 parts by weight of a water based acrylic resin, 20 to 50 parts by weight of a water based amino resin and 5 to 30 parts by weight of an amine-modified epoxy resin.