Trust in Chrome Free Technology
There has recently been speculation that chrome free technology used in the pretreatment of architectural aluminium is not as robust as that of its chrome based alternative. QUALICOAT, the largest membership driven standard, specified across the globe, disagrees.
First we need to look back at why chrome-free systems were developed, when we know that chrome based pretreatment systems work so well. Key to any architectural powder coating finish is the quality of its pretreatment, whilst the thickness of powder finish is important, without a quality pretreatment in place, the substrate will not be protected from corrosion, and the powder paint will not adhere well to the substrate. Recently it became apparent that the use of chrome based chemicals can lead to an increase in some cancers. On this basis, and the fact that chrome based systems would eventually be banned by the EU, chrome free systems were developed.
Early chrome-free pretreatment systems, introduced some 20 years ago, offered very little margin of error during processing. Today, chrome-free systems have advanced to the level where its experienced use is comparable to its chrome based cousin. This is a fact borne out by QUALICOAT’s own sample testing from its global membership over the last few years.
So is chrome-technology suitable for external architectural powder coating?
Definitely. Virtually all of QUALICOAT members in continental Europe offer chrome-free systems, whist in the U.K. more than half of QUALICOAT members have made the switch from chrome to a chrome-free pretreatment. There is no distinction made between indoor and outdoor architectural powder coating.
Today’s chrome-free systems, that are QUALICOAT approved, and that are applied by Applicators who are QUALICOAT approved, are robust and worthy of specification in any location. QUALICOAT have released a technical guidance note explaining all, which is available from the QUALICOAT U.K. & Ireland website at http://www.qualicoatuki.org/assets/05_chrome_free.pdf
Copies of the current fifteenth edition of the QUALICOAT Standard, complete with amendments and updates, is freely available through the UK Association website.