The present invention is directed to a method for forming a composite coating on a substrate. The method comprises:(A) applying a first, waterborne coating composition to a surface of the substrate, the composition comprising:(a) a polymeric component containing acid functional groups and an additional, different functional group;(b) a curing agent having functional groups reactive with the additional functional groups on the polymeric component; and(c) microgel particles different from the curing agent, prepared from a diamine and an acid functional polyisocyanate, wherein the polyisocyanate contains an average of 0.75 acid functional groups per molecule and the wherein the polyisocyanate has at least three isocyanate functional groups, to form a substantially uncured first coating thereon; and(B) applying a second coating composition to the uncured first coating, to form a substantially uncured secondary coating thereon.;Also provided are coated substrates prepared using the above method.
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