A metallic article is coated with an adherent polymer film by contacting the metallic article with an aqueous bath containing an anionic surfactant stabilized emulsion of a synthetic resinous film forming composition and an oxidizing acid. Interaction of the oxidizing acid and the metallic article produces ions at the surface of the article which ions in turn cause coagulation of the emulsion polymer at the bath-article interface and, thereby, the formation of a coating of the polymer on the surface of the article.
A lubricating coating is applied to a metallic surface by treating the surface with an acidic aqueous coating composition comprising a coating-forming lubricant and an oxidizing agent.
An organic coating bonded to a metallic substrate and applied from an acidic, aqueous coating composition containing epoxy resin solids and a cross linking resin. The resin solids are incorporated into the coating composition as an emulsion in a water insoluble solvent, so that the reactive resin is isolated from the acidic aqueous medium. The novel composition and the novel method result in a coating which can be pigmented and which can be utilized as a final corrosion resistant coating or as an undercoat for a later applied finish coat.
An acidic aqueous coating composition having dispersed therein solid resin particles and of the type which forms on a metallic surface immersed therein a resinous coating which increases in thickness or weight the longer the time the surface is immersed in said composition, said composition being characterized by having therein (A) particles of resin which are prepared by polymerizing (i) a conjugated diene, (ii) CH.sub.2 .dbd.CHR wherein R is an aryl or cyano group, (iii) a vinyl halide, and (iv) a monoethylenically unsaturated monomer having a functional group or (B) resin particles which are substantially chemically and physically homogeneous, and wherein said composition has little or no surfactant in the aqueous phase of the composition.
An acidic aqueous coating composition containing an organic coating-forming material forms on a metallic surface immersed therein a coating, the weight or thickness of which is related to the time the surface is immersed in the composition. The coating composition, which tends to become unstable as a result of the build up of metal ions in the composition, is stabilized by removing the metal ions with an ion exchange material. Also, in maintaining stability, anionic and/or nonionic surfactants or dispersing agents, which are present in the composition to disperse the organic-coating forming material, are added to the composition in an amount in excess of that which is added to replenish the organic coating-forming material as it is consumed during use. Also, coating compositions treated with the ion exchange material tend to produce coatings which have a textured or grainy appearance. The texturing of coatings can be avoided by contacting the coating composition with the ion exchange material in the presence of a cationic surfactant or an amphoteric surfactant which has cationic properties in the acidic aqueous coating composition, or other material which maintains the relatively small particles of the organic coating-forming material in the composition.
Method and composition for applying an organic coating to a metallic surface, the surface being contacted with an acidic aqueous coating composition comprising an organic coating-forming material, fluoride, and ferric iron, wherein the thickness and/or weight of the coating formed on the surface can be controlled by varying the time the surface is immersed in the composition.
