Reducing the cracking of autodeposited coatings

Claim 1

In an autodepositing coating process wherein an organic coating is formed on a metallic surface in a bath containing an acidic aqueous coating composition containing dispersed solid resin particles such that without external electricity the thickness of the coating formed increases during the time the metallic surface is immersed in the composition wherein the volume of the coating composition in the bath is maintained by periodic or continuous replenishing of the bath components as metal is processed through the bath and wherein cracks are formed in the coating produced on said metallic surface immersed in a replenished bath, the improvement which comprises maintaining an environment substantially free of oxygen in the area of the metal surface having a wet coating thereon during at least a part of the time after said coated metal surface is withdrawn from the coating composition and before the coating is fused to prevent the formation of cracks in the wet coating, wherein the substantially oxygen free environment is maintained by surrounding the metallic surface with an inert gas.