Patent ID: 10730219

Abstract:
To provide a method for producing a fluororesin film, whereby defects due to deterioration (such as fish-eyes due to gelation) of a melt-processable fluororesin are less likely to occur during the production. A method for producing a fluororesin film, which comprises extruding a fluororesin material containing a melt-processable fluororesin through an extruder die, wherein the temperature of the extruder die is from 305 to 355° C., and the average flow velocity v0.95 of the fluororesin material as obtained by v0.95=Q0.95/A0.95, is at least 1×10−4 m/sec. Here, when the distance from the flow inlet 22 of the extruder die to the end of the manifold 24 of the extruder die is set to be x=1, Q0.95 is the flow rate (m3/sec) of the fluororesin material flowing in the manifold 24 at a position of x=0.95 from the flow inlet 22, and A0.95 is the cross-sectional area (m2) of the manifold 24 at a position of x=0.95 from the flow inlet 22.