Protective film for temporarily lamination to electromagnetic wave shielding sheet, method for producing the same, and electromagnetic wave shielding sheet

Abstract

The present invention is to provide an electromagnetic wave shielding sheet with a protective film that is temporarily laminated on a copper mesh layer for shielding electromagnetic waves, the electromagnetic wave shielding sheet is not discolored even after long-term use, especially at high temperature and high humidity, while the protective film exhibits appropriate adhesion properties. To achieve the object, there is provided an electromagnetic wave shielding sheet comprising a transparent substrate, at least a copper mesh layer provided on one surface of the transparent substrate and a protective film temporarily laminated to the copper-mesh-layer-side surface, the protective film comprises a support and an adhesive layer containing a polymer having repeating units derived from an acrylic ester and/or a methacrylic ester on the support, and the amount of free organic acids in the adhesive layer is an amount which makes 10 or less the color difference ΔEL*a*b* of the copper-mesh-layer-side surface of the electromagnetic wave shielding sheet before and after the adhesive layer surface is laminated on the copper-mesh-layer-side surface and they are left for 200 hours in an atmosphere of a temperature of 60° C. and a relative humidity of 95%.

Dependencies are inferred from the claim text.