Patent ID: 6458235
Filing Date: 2002-10-01
Classification: B05D,B32B

Abstract:
Method of coating a metallic iron-containing strip with thernmoplastic coating material, comprising:preheating the strip to have, just prior to coating a first side of the strip, a temperature between 70Â° C. and 150Â° C.; coextruding, in a first coating station a molten sheet comprising a polyolefin covering layer and a modified polyolefin adhesion layer; coating the first side of the strip with the coextruded molten sheet in the presence of ozone by pressing the coextruded molten sheet with the adhesion layer against the surface of the strip to form a strip coated on one side with a coating having a thickness of 3 to 20 &mgr;m; transporting the strip coated on one side to a second coating station and heating the strip to have a temperature, just prior to coating a second side of the strip, between 70Â° C. and 120Â° C.; coating a second side of the substrate with a molten sheet comprising polyolefin extruded in the second coating station by pressing the extruded molten sheet against an uncoated surface of the substrate, in the presence of ozone to coat the second side with a coating having a thickness of 3 to 20 &mgr;m; heating the twice coated strip to a temperature which is above the melting point of the polyolefin applied; cooling the heated, twice coated strip.