Abstract: A process for preparing fast setting varnishes for coating preferably metallic materials with highly deformable coatings by thermal treatment at temperatures exceeding 175.degree. C., preferably at 180.degree.-450.degree. C., consisting of a binding agent mixture dissolved in high-boiling varnish solvents and consisting of50-90 percent by weight of a high-molecular, hydroxyl-group containing polyester on the basis of mainly aromatic dicarboxylic acids and diols and/or triols having 4-12 carbon atoms; and10-50 percent by weight of adducts on the basis of 3-isocyanato-methyl-3,5,5-trimethylcyclohexylisocyanate blocked with .epsilon.-caprolactam; plus, if desired, varnish additives, dyes and/or pigments.