A process for producing multi-layer coatings comprising a waterborne
primer-surfacer layer and a topcoat applied thereto on substrates, in
which a waterborne primer-surfacer layer is applied from a waterborne
primer-surfacer to substrates and baked and then a topcoat is applied,
wherein the waterborne primer-surfacer has a binder solids content with a
hydroxyl number of 100 to 250 mg KOH/g and contains free or blocked
polyisocyanate as a curing agent (crosslinking agent) for the
hydroxy-functional binder(s) in a molar ratio of OH/NCO of more than 2:1
to 5:1, and wherein, after it has been applied and before baking, the
waterborne primer-surfacer layer is allowed to evaporate for 30 to 300
seconds at 15 to 40.degree. C.