Coating metal strip for use in automobile, aircraft or aerospace industry, including formation of flexible, adherent lacquer layer using aqueous dispersion of UV-crosslinkable resin, wax and corrosion inhibitor

摘要

A method for coating a metal strip involves applying anticorrosion layers (L1) and polymer-based lacquer-like layers (L2) and optionally further layer and/or lacquer layer. - (L2) is applied by coating surface with aqueous dispersion containing UV-crosslinkable, water-soluble and/or water-dispersible resin, wax, photoinitiator and corrosion inhibitor, drying and hardening. - A method for coating a metal strip for use in the automobile, aircraft or aerospace industry involves applying anticorrosion layer(s) (L1) and polymer-based lacquer-like layers (L2), sectioning the strip (before or after applying (L1) and (L2)) and subjecting the sections to forming, joining and/or coating with a (further) (L2) layer and/or a lacquer layer. Application of (L2) involves coating the surface with an aqueous dispersion (A) containing UV-crosslinkable, water-soluble and/or water-dispersible resin(s) (I), wax(es) (II) as forming additive, photoinitiator(s) (III) and corrosion inhibitor(s) (IV), drying and hardening to give layer (L2) of thickness of up to 10 mu m. In a mandrel bending test according to DIN ISO 6860 (but without cracking the test surface) using a mandrel diameter of 3.2-38 mm, (L2) shows no (less than 5%) signs of corrosion when immediately tested in a saturated atmosphere according to DIN 50017 KFW over 240 hours. - An INDEPENDENT CLAIM is included for a variant on the process in which the application of (L1) is omitted.