Method for making a durable wood-plastic composite panel upon which plastic films may be readily and securely adhered
An apparatus and method for fabricating a panel from a molten composite material, and a panel product fabricated accordingly. Two platens in spaced relation define a gap which decreases uniformly from first ends of the platens toward second ends of the platens. Molten composite material is moved through the decreasing gap to compress the material between the platens. Cooling drums cool the composite panel shortly after extrusion. A mesh is rolled into a surface of the extruded panel; the screen remains partially exposed on the panel surface to provide a panel surface amenable to the application of adhesives.
1. A method for making a composite panel from a molten composite material, comprising:
providing a pair of spaced-apart planar platens converging toward each other from first ends of said platens to second ends of said platens, thereby defining a narrowing space there-between;
disposing said first platen ends proximate to a material extrusion die;
extruding molten material from the die for movement to said first platen ends;
pressing a mesh into a surface of the molten material;
moving the molten composite material in said narrowing space from said platen first ends toward said platen second ends, thereby constantly compressing said molten composite material between said converging platens;
cooling the molten material while constantly compressing the molten material between said pair of converging platens;
delivering a composite panel from between said second ends of said platens, said panel having a working surface with said mesh partially embedded therein;
leaving portions of the mesh exposed above the working surface; and
attaching an appliqué layer to the working surface by using an adhesive to adhere the appliqué layer to the exposed portions of the mesh.
2. The method of claim 1 , wherein extruding molten material comprises extruding a molten material comprising ground wood particles and thermoplastic particles.
3. The method of claim 2 wherein pressing a mesh comprises rotating a mesh roller against the mesh and the molten material.
4. The method of claim 3 further comprising cooling the mesh roller with a cooled oil flow.
5. The method of claim 2 wherein pressing a mesh comprises pressing a metal wire screen.
6. The method of claim 2 further comprising evening an upper surface of the molten material with a pre-compression roller as the material emerges from the extrusion die.
7. The method of claim 6 further comprising cooling the pre-compression roller with a cooled oil flow.
8. The method of claim 5 wherein pressing a metal wire screen comprises pressing a wire screen having a Tyler Equivalent mesh size of 18×16.
9. The method of claim 2 wherein the step of attaching an appliqué layer is taken without previously flaming the working surface.
10. The method of claim 5 wherein leaving portions of the mesh exposed comprises leaving exposed up to about 50% of a circumference of any wire comprising the metal wire screen.
11. The method of claim 2 wherein attaching an appliqué layer to the working surface comprises attaching a layer of prismatic reflective sheeting.