PPGI is pre-painted galvanized steel, PPGL is pre-painted aluminized zinc steel also known as pre-coated steel, color coated steel etc. Using Hot Dip Galvanized Steel Coil as the substrate, PPGI is made by first going through surface pre-treatment. Then the coating of one or more layers of liquid coating by roll coating, and finally baking and cooling. PPGI coil is short for pre-painted galvanized steel coil. It uses a hot-dipped galvanized steel sheet as substrate and be coated with several layers of organic coatings to protect it from rusting.