METHOD FOR MANUFACTURING POLARIZER PROTECTIVE FILM, POLARIZER PROTECTIVE FILM, POLARIZING PLATE, AND OPTICAL DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method capable of manufacturing a polarizer protective film which is excellent in toughness and adhesiveness and suppressed in the occurrence of retardation.SOLUTION: The method for manufacturing a polarizer protective film includes the steps for heating a film formation material including a thermoplastic resin serving as a base material and a granular elastomer and for extruding the heated film formation material in the shape of a sheet by a pair of rolls whose contact surfaces are metallic. A linear pressure for sandwiching the film formation material by the pair of rolls in the extrusion step is 5 N/cm or more and less than 150 N/cm. It is preferable that the method further includes a step for drawing a sheet body after the extrusion step a little and it is preferable that the drawing ratio is 0.01% or more and 5% or less. It is preferable that the content of the thermoplastic resin in the film formation material is 50 wt.% or more and 95 wt.% or less and the content of the granular elastomer is 5 wt.% or more and 50 wt.% or less.