Extrusion coating process for making protective and decorative films

Abstract

A process for making a protective and decorative surfacing film comprises extrusion coating a solid polymeric material from an extruder die to form an optically clear first layer of uniform film thickness on a smooth surface of a carrier sheet traveling continuously past the extruder die opening. The extrusion coated first layer is immediately cooled on the carrier sheet to harden it, followed by applying a pigmented second layer in thin film form to the first layer to form a composite paint coat in which the first and second layers are bonded to each other. The composite paint coat is then transferred to a supportive backing sheet or substrate panel, after which the carrier sheet is separated from the paint coat, to expose the outer surface of the first layer as a high gloss surface with a high distinctness-of-image, providing a transparent protective outer coat for the underlying pigmented second layer. The pigmented second layer can be solvent cast and dried or extruded and hardened as a separate coating on the extrusion coated first layer. Alternatively, the second layer can be formed with the first layer as a coextrusion which is extrusion coated onto the smooth surface of the release coated carrier sheet that travels past the extruder die.