Abstract: A multiple outlet flat film die apparatus and process which extrude separate streams of material to form any of various composites which may involve joining of similar or dissimilar materials, which includes individual manifold chambers separated from each other by heat insulating means inbetween. The heat insulating means in between such as for example heat insulating material between plates retards heat transfer between the materials. Each manifold is tapered toward its own die mouth; has separate melt inlets adapted for center, top and/or end feed operations; has separate pre-land and final land surfaces leading to individual outlet openings for precise control of melt flow; and has separate heat control means allowing precise temperature control for each melt as it flows toward the die. Temperature differentials may be extensive and may approach the difference between the original temperature of the melt delivered to each manifold. Heat differentials of 0.degree. to 200.degree.F. are an example.

Abstract: A dual outlet extrusion flat film die assembly for various thermo-extrudable materials includes split manifold chambers separated from each other by a rigid centerplate. Each portion of the die in the direction behind the flow materials includes a heat sink slot behind the manifold. Each manifold tapers toward its own die mouth; has separate melt inlets adapted for center, top or end feed operations; has separate pre-land and final land surfaces leading to individual outlet openings for precise control of melt flow; and has separate heat control means allowing precise temperature control for each melt as it flows throughout the die. Temperature differentials ranging from O.degree. to 200.degree.F. are obtainable between the extruded layers. A differential push-pull adjustment system for each movable lip of each outlet opening includes opposed alternatingly staggered thimble bolts to precise control of each individual layer profile.