The basic concept of color-coated sheet laminates: take cold-rolled strip steel, galvanized strip steel (electro-galvanized, hot-dip galvanized) as the substrate, and use the roller coating method, one or more layers of liquid coatings, and baking cooling plates as the coating steel plate. At present, there are back paint (primer) and top coat (front) coatings in the mainland. Generally, there are one layer of back paint, two layers of top paint, and two layers of business top paint. Since the coating can have different colors, the coated steel sheet is often called color coated steel sheet. Color-coated boards for building materials can be divided into three categories: internal use, external use and other uses: more than 60%-70% of them are external boards, which are mainly used as roof cover boards and external wall boards. The organic coating board for building materials has been exposed to wind, sun, rainforest, cold and heat for a long time. In addition, beautiful tones, novel styles, rich textures, and coordination with the building as a whole and its surrounding environment are also required.