Abstract: A three-layer extrusion of polymer material forming a decorative composite panel, with an outer and inner solid polymer layer of relatively high density, and a central polymer layer of lower density or a filled central polymer layer of higher density. The three layers are coextruded, and each face of the center layer is fused to a respective face of the outer and inner solid polymer layers, forming a solid panel that meets ASTM standards for Rigid Poly(vinyl chloride) Siding. The three layer panel can be coextruded with two extruders (ABA configuration) or three extruders (ABC configuration). The specific layer compositions result in cost savings and material reductions or in performance enhancement of the panel or in providing a higher heat distortion panel or for scrap reclamation.

Abstract: Siding formed of thermoplastic resin material and characterized by an embossed grain texture, and by low light reflection and high impact strength. Method and apparatus are provided incorporating various steps and devices for imparting a grain texture by embossing and for reducing the gloss and increasing the impact strength, notwithstanding the embossing.

Abstract: Extrusion equipment is disclosed, including an extrusion die structure having a die passage formed to provide improved flow conditions and control including equalization of the flow of the plasticated resin material in a zone close to the lip portion of the die.