PROCESS FOR MANUFACTURING STRETCHED POLYTETRAFLUOROETHYLENE FILM, AND STRETCHED POLYTETRAFLUOROETHYLENE FILM

摘要

A process for manufacturing a stretched polytetrafluoroethylene (PTFE) film, comprising: subjecting a resin composition, which has been obtained by mixing an emulsion of a PTFE (A) having a number-average molecular weight of 5 × 106 or more and an emulsion of a PTFE (B) having a number-average molecular weight of 1 × 106 to 4 × 106 so as to give an (A)/(B) solid content ratio of the PTFE (A) to the PTFE (B) of 99/1 to 10/90, to compression molding under a reduced-pressure atmosphere in a molten state to form a film; and subjecting the film to melt stretching.