| 摘要 |
Method of coating a metallic substrate (1) with thermoplastic coating material, comprising a preheating the substrate in such as way that, just prior to coating, it is at a temperature between 70 .degree.C and 150 .degree.C, preferably between 100 .degree.C and 130 .degree.C in the case of a coating containing polypropene and between 80 and 110 .degree.C in the case of a coating containing polyethene; coextrusion, in the first coating station of a sheet (6) comprising a polyolefin covering layer and a modified polyolefin adhesion layer; coating of the substrate (1) with a molten sheet in the presence of ozone by pressing it with the adhesion layer against the surface of the substrate; transportation of the strip (9) coated on one side to a second coating station and heating the strip so that, just before coating, the strip is at a temperature between 70 .degree.C and 130 .degree.C, preferably between 80 .degree.C and 120 .degree.C, if the coating layer applied in the first coating station is polypropene and between 80 and 110 .degree.C if the coating layer applied at that point is polyethene; coating of the substrate with a molten sheet extruded in the second coating station by pressing it against the uncoated surface of the substrate, use being made of the presence of ozone; heating ofthe coated substrate so that it assumes a temperature which is above the melting point of the polyolefins applied; cooling of the coated substrate.
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