In addition to the substrate and substrate coating, the more important thing for selecting prepainted galvanized steel coil is the coating. Coating is the protective layer of cladding material.
As long as the coating is not damaged, it is impossible to affect the substrate inside the coating.
The main function of coating reflected in visual effects and protection functions, and its painting can be divided into organic coatings and inorganic coatings. The organic coatings have bright color, the inorganic coatings are generally light-colored, and it has better chemical properties and resistance to UV performance than organic coatings. The common top paint type of prepainted galvanized steel coil are PE top paint, SMP top paint, HDP top paint and so on. The commonly used type of prepainted galvanized steel coil in HUADA is PE top paint. Different types of top paint have some difference in hardness, adhesion and durability, and users can purchase based on these aspects.
The coating of prepainted galvanized steel coil divides to top paint coating and bottom paint coating. For the choice of bottom paint, epoxy resin is better if users emphasis on adhesion and corrosion resistance. Then if the users concerned more about the flexibility and UV resistance, then select the polyester bottom paint or polyurethane bottom paint.