Abstract: Method of producing coating films from coating formulations which are free-radically polymerizable under thermal initiation, characterized in that it comprises at least the following steps: a) coating of the substrate with the coating formulation b) thermally initiated curing of the coating formulation c) elimination of quality deficiencies in the cured coating material d) curing of the coating material to completion by UV exposure, and also to a coating formulation suitable for this method, comprising monomers containing ethylenically unsaturated groups and thermal free-radical initiators, the coating formulation being substantially free from UV initiators and the hardness of the coating material after thermal curing and subsequent UV irradiation being higher by at least 15% than after thermal curing without UV irradiation.