TECHNOLOGY FOCUS - POLYMERS - Preferred Material: The organic resin based coating materials (I and II) contains 0.2-5 wt.pts of inner wax with respect to 100 wt.pts of 400-1000C polyester resin, as main component. The organic resin based coating material (III) contains 0.1-4 wt.pts of inner wax, and 1-20 wt.pts of spherical nickel filler having particle size of 1-2 times of the film thickness of the electroconductive coating film, with respect to 100 wt.pts of 400-1000C polyester resin. Ratio of breadth and length of the nickel filler is 0.7-1. The mixing ratio of the wax in coating material (III) is 0.2-0.8 times of the mixing ratio of wax in coating material (II). Preferred Thickness: The thickness of undercoat, top-coat layer, and electroconductive film is 1-20 mum, 5-30 mum, and 1-20 mum, respectively.    TECHNOLOGY FOCUS - POLYMERS - Preferred Method: The lubricating coating film and electroconductive coating film are formed at the aluminum plate surface having chromate or non-chromate layer of reaction mold or coating mould formed by the surface treatment method. EXAMPLE - An aluminum-magnesium alloy plate subjected to chromium phosphate surface treatment was used. An under layer of 5 mum thickness was formed on treated surface of the aluminum plate using coating material containing polyethylene wax (in weight parts) (1) and polyester resin (average carbon number of 451) (100). Subsequently, top-coat layer of 10 mum thickness was formed on the undercoat using a coating material containing polyethylene wax (1), pearl pigment (5) and polyester resin (average carbon number of 451) (100) to form a lubricative coating film. A conductive coating film of 2 mum thickness was formed on other surface of the aluminum plate using a coating material containing spherical nickel filler (with particle diameter of 4 mum) (20), polyethylene wax (0.5) and polyester resin (average carbon number of 451) (100), and dried at 100degreesC, to obtain a double-side precoated aluminum plate. Press formability, electroconductivity, and corrosion resistance of the obtained aluminum plate were found to be favorable. Adhesion of the lubricative coating film, and conductive coating film were found to be favorable.