Abstract: An illuminated sign letter structure made up of an extruded plastic strip having a metal foil encased therein. One end of the strip is enlarged and has a ledge projecting outwardly from the strip. The opposite sides of the ledge are parallel and smooth for receiving the edges of a letter-form. The extruded plastic strip is formed into a letter shape and a letter-form of the letter shape is fixed in the frame to engage either the inner or the outer parallel, smooth ledge side. The metal foil may be straight or the end of the foil at the enlarged end of the extruded strip may be bent inwardly into the enlarged end.

Abstract: A process for extruding resilient, impact resistant thermoplastic strips having a metallic appearance by providing a non-metallic film strip of a material selected from the group consisting of polysulfones and polyether sulfones and having a vapor deposited metallized surface, the film strip having melting and deformation temperatures higher than those of a transparent thermoplastic to be extruded thereon and a resiliency and an elasticity at least as high as the resiliency and elasticity of such transparent thermoplastic when extruded thereon and, while feeding such film strip through a cross-head die, extruding the transparent thermoplastic about the metallized film strip and the resilient, impact resistant thermoplastic strip having a metallic appearance produced thereby.

Abstract: A sign letter structure for use in an illuminated sign and a composite extruded thermoplastic strip conforming to the periphery of a generally flat letter-form making up the sign, the extruded strip having parallel longitudinally extending spaced opaque sections with a transparent thermoplastic section therebetween, the perimetrical edging of the strip extending inwardly of the frame with the front surface of the edge in contact with the front surface of the letter-form, the transparent section having a convex outer surface and a ridged inner surface for picking up light rays and for diffusing such light rays after they have passed through the transparent section.