TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Properties: The adhesive strength is 0.1 MPa or more and the peeling strength is 5 N/mm or less. The hard and soft cladding materials are welded thermally. The heat conductivity of exterior layer of the soft cladding material is 1 or less, and the melting temperature is higher than that of the thermobonding layer of the hard cladding material. The heat conductivity per area of the layer formed by laminating the exterior layer and metal layer of the hard cladding material is 1000 W/m-2K-1 or more. The amount of heat conduction per area of metal layer is 50000 Wm-2K-1 or more, and the amount of heat conduction per area of exterior layer is 1050 Wm-2K-1 or more. The exterior layer of hard cladding material has a thickness of 115 mu m or less.    TECHNOLOGY FOCUS - METALLURGY - Preferred Layer: The metal layer of hard cladding material consists of tin, zinc, nickel, aluminum, copper, iron, and/or stainless steel, and has a thickness of 330 mu m or less.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The thermobonding layer of hard cladding material comprises ethylene vinylacetate copolymer, ethylene acrylic acid copolymer, ethyl acrylate copolymer, methyl acrylate copolymer, methacrylic acid copolymer, methylmethacrylate copolymer, polyacrylonitrile, ethylenevinyl alcohol resin, polyamide resin, polyester resin, acid-modified polypropylene, and/or ionomer. The thermobonding layer of soft cladding material comprises unextended polypropylene and/or unextended polyethylene. The thermobonding layer of hard cladding material and exterior layer of soft cladding material comprise different materials chosen from extended resin material of polyolefin, polyamide, polyimide and/or polyester. The extended polyamide is nylon 6. The extended polyolefin is polypropylene or polyethylene. The extended polyester is polybutylene terephthalate, polyethylene terephthalate, and/or polyethylene naphthalate. The exterior layer of hard cladding material consists of polyamide, polyester or polyolefin.