Is aluminum flashing coil colored coated aluminum coil? Yes most of the time, but color coating is not the only surface treatment method for it. Judged by the word “flashing”, we sense that the surface of the coil should be made into water-proof roofing and valley panels for houses. As known to all, although aluminium coils are renowned for their resistance to water corrosion, mill finished rolls are not strong enough to withstand long-term rains in natural conditions. Therefore, the surface of aluminum flashing coil must be further treated to obtain sufficient weather resistance. What are relative surface treatment methods, then?
Basically regular methods at present include anodizing, color coating and filming. The substrate coil can be either mill finished or embossed, since some clients need the aluminum flashing coil to be embossed for special decorative or application purposes. Anodizing, a chemical method, is to coat a layer of dense aluminum oxide on the surface of aluminum and aluminum alloy to prevent further oxidation. Although the chemical properties of anodized aluminium sheets and rolls are the same as oxide aluminum, their mechanical properties are much better. The anodized film is hard in strength and excellent in erosion resistance, lasting years in natural conditions. The process of color coating of aluminium coil rolls can be realized by both chemical and physical methods. The first is anodizing, during which aluminium pieces can be dyed by electrolytic coloring. The other is paint coating, in which the pieces are sprayed (powder, electrostatic etc) with pe or pvdf paints. These paint coatings, especially pvdf, last decades without pealing or fading. Filming seems to be a little simpler. It’s realized by film the surface of aluminium flashing coils with special water and weather resistant materials.
That’s how brown, black, gray and white aluminum flashing coil rolls come into being. Each method, however, has its own advantages. If you need long service life, pvdf coating and anodizing would be a better choice.