Composite plastics film with metal and protective coating on both sides - having protective coating contg. electroconductive pigment and use as cable covering acting as water vapour barrier and electromagnetic shield

摘要

Composite metallised plastics film (I) with protective coatings has a 30-100nm thick metal coating (II) on both sides, each with a pigmented protective coating (III) contg. electroconductive pigment (IV). (I) has a surface resistivity (Rs) of max. 10 power 4 ohm/sq. (III) is pref. 0.5-5 microns thick and contains 5-30 vol.% (IV). The film pref. consists of polyester, polypropylene, polyethylene, PVC, polyamide or polycarbonate; and (II) of Al, Cu, Ni, Ag, Fe or an alloy of these. (I) pref. has R2 = 0.5 to 10 power 4 ohm/sq.; and water vapour permeability = less than 4.5 g/m2.bar.day (38 deg.C/85% RH) (claimed). USE - (I) is used as water vapour barrier in electric cable coverings (claimed). It also acts as electromagnetic shield.