NOVELTY - A wrapping material (1) has heat-resistant-resin stretched film layer (2), thermoplastic resin unstretched-film layer (3), and aluminum foil layer (4). Aluminum foil layer has a foundation membrane (11,12) containing chitosan and/or its derivative. Aluminum foil layer is a film formed by processing surface of aluminum foil by surface-treatment agent containing metallic compound of metal(s) chosen from titanium, hafnium, molybdenum, tungsten, selenium, cerium, iron, copper, zinc, vanadium and trivalent chromium, preferably trivalent chromium.    USE - Wrapping material is used for case for electronic component (all claimed) e.g. capacitor and lithium ion secondary battery used as power supply for notebook personal computer, video camera, mobile telephone and electric vehicle.    ADVANTAGE - The electronic component formed using the wrapping material has excellent adhesiveness, moldability and gas-barrier property.    DETAILED DESCRIPTION - A wrapping material has heat-resistant-resin stretched film layer (2), thermoplastic resin unstretched-film layer (3), and aluminum foil layer (4) arranged in the interlayer of films (2) and (3). The dry laminate of aluminum foil layer and thermoplastic resin unstretched-film layer is carried out through an adhesive bond layer containing thermoplastic elastomer. The aluminum foil layer has a foundation membrane formed on one surface of the inner side layer of an aluminum foil. The foundation membrane contains chitosan and/or its derivative. The aluminum foil layer is a film formed by processing the surface of aluminum foil by a surface-treatment agent containing metallic compound of metal(s) chosen from titanium, hafnium, molybdenum, tungsten, selenium, cerium, iron, copper, zinc, vanadium and trivalent chromium, preferably trivalent chromium. INDEPENDENT CLAIMS are included for the following:    (1) case, which is formed by performing deep draw forming or stretch formation of wrapping material, and molding in specified shape; and    (2) electronic component, which has an electronic main component and case which surrounds the electronic main component.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view of wrapping material.    Wrapping material (1)    Heat-resistance-resin stretched film layer (2)    Thermoplastic resin unstretched-film layer (3)    Aluminum foil layer (4)    Adhesive bond layers (5,6)    Aluminum foil (10)    Foundation membranes (11,12)