Montmorillonite nanofiller in amout of 1 wt. % was used to fill, water-thinnable epoxy compns. prepd. from a liq. epoxy bisphenol A resin and a self-emulsifying curing agent (an epoxy resin-amine adduct). Ca montmorillonite was modified with com. poly(oxypropylene)diamine ammonium derivs. The montmorillonite did not affect the spreadability; it shortened slightly the pot life and room-temp. drying time of the coating system. The filled coatings adhered as wen to a steel substrate as did the unfilled; they were more resistant to scratch, but slightly less water-resistant and more water uptaking.