It is a composite metal plate, including galvanized or galvanized metal substrate, chemical treatment layer polymer conversion layer, high weather resistance and anti-corrosion film layer (PVDF fluorocarbon film). It is a cost-effective building roof. And wall maintenance materials, materials that meet the various performance combinations required by the modern construction industry, and film-coated steel plate products are firmly combined with high-weather-resistant engineering resin films on the basis of making full use of the rigidity and strength advantages of metal substrate materials. Due to the weather resistance, ultraviolet resistance, humidity and heat aging resistance, acid and alkali corrosion resistance, oxidation resistance (sodium hypochlorite and ozone), and fire resistance of the coated steel plate, the mechanical, chemical, physical and other comprehensive properties of different component materials are exerted to a greater extent. widely used.