| 摘要 |
1,161,097. Plastics/metal laminates. DOW CHEMICAL CO. 1 Nov., 1966, No. 48894/66. Heading B5N. [Also in Division B2] In a process for adhering an organic thermoplastic material to a metal substrate the surface of the substrate is treated with an aqueous inorganic acid solution containing no more than the usual trace amounts of salts and containing hexavalent chromium and/or a solution containing an aliphatic carboxylic acid, the metal is rinsed with water, the resulting treated metal is dried, a layer of the organic thermoplastic material is placed on the treated metal surface and the resulting assembly subjected to heat and pressure. In one process described an aluminium substrate is immersed in a substantially salt-free aqueous inorganic acid solution containing chromium trioxide, is rinsed, placed in a second solution containing an aliphatic carboxylic acid, rinsed, and dried. A thermoplastic film is then adhered to the substrate using heat and pressure. If desired either the treatment of the substrate with the inorganic acid solution or the second solution may be omitted. The metal substrate is alternatively tinplate, nickel, iron, galvanized metal, magnesium or combinations thereof. The thermoplastic film may be high or low density polyethylene, polypropylene, polybutene-1, copolymers of ethylene and propylene, or a copolymer of ethylene and maleic anhydride and may contain a filler, e.g. carbon black. The inorganic acid may be phosphoric acid and the aliphatic carboxylic acid may be maleic, acrylic, polyacrylic, citraconic, fumaric, methacrylic, crotonic, glutaric, itaconic, or maleamic acid. The thermoplastic layer may be applied by extrusion coating, as a powder, or as a film and in the latter case may be formed by compression moulding in a press where it is first heated and then cooled. The plastic/metal article produced may be used in making wires and cables, pipelinings, corrosion and chemical resistant protective coatings, packaging materials, or printed circuit boards. |
