Forming laminated billets from individual billets

Claim 1

A continuous process of forming a thermoplastic laminated billet comprising: providing a mold conveyor belt on which a plurality of mold bodies are attached, each mold body having a mold cavity defined downwardly therein, said mold body having a bottom side electrode, providing a stamping means indexed with the movement of the mold conveyor belt so that a stack of individual billets cut from a stack of individual thermoplastic sheets falls into said mold cavity, providing a top electrode conveyor belt having top side electrodes, the movement of the top electrode conveyor belt and the mold conveyor belt being indexed such that a top electrode may be positioned over a mold cavity, simultaneously extruding a plurality of said individual thermoplastic sheets, cooling the below their softening points, and bringing sheets together to form the sheets into a stack of individual sheets not bound to one another, said stack comprising one or more dielectrically heatable sheets, and one or more dielectrically non-heatable sheets; and each sheet is located in a flat planar manner relative to one another, simultaneously cutting a stack of said individual billets from the stack of unbound individual sheets and dropping said billets downward into said mold cavity to form a stack of individual billets having the same sequence of individual billets as the individual sheets, and a stack of individual webs; separating the webs from each other and recycling each web to its respective sheet extrusion step; positioning the top electrode over the stack of billets carried in the mold cavity, applying a RF field to the billets located between the top electrode and bottom electrode and dielectrically heating the heatable billets with one or more frequencies of radiation between about 0.1 MH z and about 3000 MH z so that the heatable billet melts and only the surface of the non-heatable billet closest to the heatable billet melts; and applying pressure to said stack of billets to cause them to adhere to each other and form a laminated billet.