Moistureproof multilayered film

摘要

A moistureproof multilayer film, including a composite film having a non-moisture absorbing resin layer and a vapor deposited film of an inorganic oxide or a metal formed on at least one side of the non-moisture absorbing resin layer, the multilayer film having such a layer structure where the vapor deposited film surface of the composite film is laminated through an adhesive layer on a vapor deposited film surface of another composite film or a surface of another non-moisture absorbing resin layer, wherein a total number (n) of the deposited films laminated adjacent to the adhesive layer is 2 to 8, and wherein a moisture permeabihty (W; unit: g/m<2>.day) as measured under conditions of a temperature of 40° C. and a relative humidity of 100% satisfies a relation represented by equation W<=(1/n)x0.20, and a method for producing the moistureproof multilayer film including heat-treating the multilayer film in a hot dry atmosphere having a temperature lower than 140° C. but not lower than 55° C. for at least 10 hours.