‘Increased Durability for Architectural Aluminium’

Through it’s network of members across the globe, Qualicoat continue to work closely with the developers of powder systems, pre treatment systems and applicators to offer sustainable finishes for aluminium profiles. Bringing all three processes together under one Quality label ensures that each element works perfectly together. By prescribing ‘Qualicoat’ at tender stage, a specifier can be assured of a high quality and long lasting finish.

Many current powder coat finishes can carry guarantees of up to 30 years with given colour and gloss retention variations. With regular cleaning and minimal maintenance, the finish will remain in place to protect the aluminium whilst offering a lasting aesthetic appearance on the building.

Polyester powder coat finishes offer the best value for the building owner, whilst giving good life expectancy when specifiers choose to source their finishing from a Qualicoat approved applicator. However, buildings being constructed today are expected to last much longer, finishes are expected to last longer with less maintenance, colours are expected to remain constant. All these issues have a direct influence on the sustainability of a building.

The future of powder coating aluminium is already here, it has been for a while, and the the technology just continues to evolve and improve.

The most widely used system of the past 30 years are what are known as Class 1 powders, these are TPA Polyesters, materials that are Polyester based and during the stoving process crosslink with suitable agents to form a stable coating once cured. These are sometimes known as ‘Standard Durable’ powders.

For the majority of uses today Class 1 is adequate in the UK’s temperate zone and, with care, will offer a long and useful life.

By changing the formulation to an IPA Polyester, which is a different form of Polyester, and combining with higher quality pigments, both gloss retention and colour retention can be substantially improved for an even longer life. Known as Class 2, or ‘Super Durable’ powders, these materials are often twice as expensive as Class 1. Once coated onto an aluminium profile, the difference in cost is minimal but gloss retention and colour stability over time is easily doubled. The increase in cost is more than outweighed by the excellent weathering capabilities of Class 2 powders and there has been a significant increase in the specification of these finishes over the last few years.

Let us now consider projects which are being constructed that are expected to last at least a lifetime, in fact 75 years or more, the need to look good, offer low maintenance with excellent weathering - enter Class 3 or ‘Hyper Durable’ powders. These powders are based on a total different chemistry and use ‘Fluoropolymers’. These can be either thermosetting (crosslinking during stoving) or thermoplastic (no crosslinking occurs) compounds.

The carbon/fluorine bond in fluorocarbon chemistry is one of the strongest molecular bonds we know of. When used in a coating, it offers outstanding weather stability combined with high chemical resistance and low soiling. This offers a finish which is easier to keep clean as it naturally repels waterborne pollutants whilst offering excellent resistance against acid pollutants in the atmosphere.

Class 3 powders are more expensive than class 2 powders as you would expect, but from the sustainability point of view, there is no equal. Class 3 powders offer exceptional life and very low maintenance which is perfect for high rise applications in the UK and overseas.

So how does a specifier decide which coating is the most suitable for any given project?

The Qualicoat organisation is based in Zurich with local organisations located in many countries across the globe In the UK, the majority of architectural powder coaters are members of ‘Qualicoat UK & Ireland’. Specifiers can contact Qualicoat’s offices in the UK, or any of its members to seek guidance on the correct specification to use for any given application.

Specifiers in the UK working on projects overseas can also specify Qualicoat in the safe knowledge that they are specifying a global standard for powder coating quality.

A complete copy of the Qualicoat standard is available from the UK associations website together with an up to date list of manufacturers and applicators at www.qualicoatuki.org. Printed literature and telephone support is available from Qualicoat UK & Ireland’s Head Office in Birmingham on 0121 601 6746.