Each Decra Noxite® tile is comprised of seven layers, designed to provide unrivalled weather protection. At the centre is the steel core, which is then hot dipped galvanised typically using zinc aluminium or zinc magnesium coatings to provide exceptional long-term durability. A chromate conversion layer is then put in place, followed by an epoxy coating. The topside of the tile is then covered with an acrylic resin and a specially developed stone granular coating.
The surface stone granules of the Decra Noxite® tiles are coated with titanium dioxide which functions as a catalyst in the process of changing the NOx molecules into harmless levels of nitrates. The process is activated when ultraviolet radiation from the sun hits the titanium dioxide particles, releasing energy for breaking down the NOx molecules. Polluted air passes over the Decra Noxite tiles where the NOx molecules are converted into harmless levels of water, carbon dioxide and nitrates, which are then washed away by the rain.
A polyester coating is applied to the underside of each roof tile. This provides further protection against wind-driven salt spray. This makes Decra Noxite lightweight roof tile the ideal choice for developments in coastal locations.
How Is The Decra Noxite Tile Protected When It Is Cut?
Decra tiles require no further protection to the cut edge providing they are cut using a Decra guillotine, reciprocating saw, tin snips or nibblers. The use of the correct cutting equipment stops any destruction occurring to the protective galvanised coating and allows a protective cathodic process to take place. An explanation of the cathodic process can be seen below.
The Science Behind The Technology
Two differing metals each with a different electric potential in direct physical contact with each other and an electrolyte (water) form a galvanic cell. Within this galvanic cell electrons from the zinc atoms which have a lower electric potential transfer themselves to the steel atoms which have a higher electric potential. This charging of additional electrons to the steel atoms protects the steel from corrosion. Corrosion will only take place in any metal when electrons from a metal atom are lost into an electrolyte (water). Since the steel atoms are being charged with electrons corrosion will not take place.