Prepainted galvanized steel sheet are mainly used in building, transport, home appliance, solar energy, furniture, etc. Especially in home appliances, the sheets are mainly used as the side door plate of refrigerators, and air conditioners, freezers, and washing machine, Using galvanized sheet, galvalume sheet or aluminum sheet as the substrate, prepainted galvanized steel sheet is made by first going through surface pretreatment, then coating for one or more layerw, and finally baking and cooling.