Prepainted steel coils(PPGI) use hot-dip galvanized sheets, electro-galvanized sheets as substrates. After surface pretreatment (chemical degreasing and chemical conversion treatment), one or several layers of organic coatings are coated on the surface, and then A product that is baked and solidified. Prepainted steel coils are lightweight, beautiful, and have good anti-corrosion properties, and can be processed directly. The colors are generally gray-white, sea blue, and brick red. They are mainly used in advertising, construction, home appliances, electrical appliances, furniture, and transportation industries.