Radically curable coating compositions and their use for coating wood substrates

A coating composition which may be radically cured at temperatures below 80.degree. C. and which comprises

• A) 50 to 95 parts by weight of an .alpha.,.beta.-ethylenically unsaturated polyester component having a viscosity at 23.degree. C. of 1,000 to 15,000 mPa.s and containing at least one polyester resin prepared by reacting at an equivalent ratio of carboxyl groups to hydroxyl groups of at most 1:1
• a) a dicarboxylic acid component containing 75 to 100 carboxyl-equivalent-% of one or more .alpha.,.beta.-ethylenically unsaturated dicarboxylic acids having 4 or 5 carbon atoms and/or their corresponding anhydrides and 0 to 25 carboxyl-equivalent-% of one or more other dicarboxylic acids having 4 to 10 carbon atoms or their anhydrides with
• b) an alcohol component containing 15 to 60 hydroxyl-equivalent-% of one or more .beta.,.gamma.-ethylenically unsaturated alkenyl ether alcohols having 6 to 14 carbon atoms and 40 to 85 hydroxyl-equivalent-% of one or more other mono- and/or dihydric alcohols having a molecular weight of 32 to 400,
• B) 5 to 50 parts by weight of compounds containing (meth)acryloyl groups and/or vinyl ether groups and having a viscosity at 23.degree. C. of 10 to 1,000 mPa.s and a molecular weight of 72 to 1,000,
• wherein the sum of the parts by weight of components A) and B) is 100, based on the total weight of components A) and B),
• C) 0.01 to 0.3 wt. %, based on the total weight of components A) to D), of a barrier agent containing one or more waxes and/or paraffins having a melting point of 35.degree. to 100.degree. C. and
• D) 0 to 10 wt. %, based on the total weight of components A) to D), of one or more plasticizers or carbamic acid resins.