Example of extruded sheet (flexible) line:

As in film processing, co-extrusion can also be utilized to create multilayer structures. Use a coat-hanger, flexible-lip die with a 1 inch land and 30-40 mil lip opening (or at least 25% greater than the desired film thickness). All flow surfaces should be hard chrome-plated and highly polished (no dead zones, nicks, or scratches). The face of the die should be tapered instead of square to permit a short die to shill roll air gap. Restrictor-bar dies are not recommended.

Cooling
Use standard 3-roll sheet-casting stacks with a 12 inch minimum roll diameter for producing nip-polished high quality film/sheet. The casting stack temperature and polish roll pressure should be balanced to eliminate sticking and maintain high quality aesthetics. The surface roughness or RMS values of the sheet casting stack cooling rollers can have a highly polished, embossed, or matte finish.

Finishing
Use sharp, rigidly mounted razor blades for trimming film edges. Use a winder with good tension control and a proximity lay-on roll. Use static reduction devices prior to winding or as needed throughout the line.