FILM EXTRUSION DIE

PROBLEM TO BE SOLVED: To provide a film extrusion die for obtaining an extrudate having a uniform crystal structure or state by reducing a residence time of a polymer in the die. SOLUTION: A side feed throttle die 10 has a polymer charging port 12, a polymer supply channel 14 and a polymer metering air gap 16 for communicating with each other via a fluid. A gap regulating plate 22 is interposed between a first plate 18 and a second plate 20 for forming the gap 16. In this case, a sectional area A2 of the channel 14 at a position near the port 12 is larger than a sectional area A3 at a position far from the port 12. A length l2 of a land of the gap 16 at the position near the port 12 is larger than l3 that of a land at a far distance from the port 12.