Advancements in powder coating
By Qualicoat UK and Ireland
As sustainability issues continue to take precedence in material specification for our new and refurbished buildings, Qualicoat (a ‘not for profit’ organisation based in Zurich, which now operates on all five continents around the globe) continues to push the boundaries of quality and durability in architectural powder coatings.
One of the key USPs for Qualicoat is that the complete supply chain is independently inspected at regular intervals to ensure conformance with the standard. Applicators are subject to twice yearly random visits by an independent test house (currently IFO) to review quality procedures, records and product performance.
So, what’s new in powder coating technology?
Textured finishes offer both a textured feel on close inspection, and introduce a deep matt appearance from a distance. On average, textured finishes offer a very low gloss level of just a 5%. Textured finishes can also be very hardwearing and are offered in a wide range of colours, all of which are supplied under the current Qualicoat specification from licensed applicators across the UK and Ireland.
Currently, the finishes are growing in popularity rapidly across Europe and the trend is set here to follow with increased specification.
Textured finishes can be supplied in a single opaque colour or be suppled as a metallic finish further enhancing the unique nature of the coating. The textured finish is especially useful if the substrate has slight imperfections that need to be hidden, or there is a need for the coating to have an anti-slip characteristic that may be required for hardware or anti-slip areas.
For the vast majority of architectural applications, the standard Qualicoat approved one coat system is perfect, where the strength of weathering is identified by the class of powder chosen. There are a few occasions where real consideration can be given to the effective use of two coats. Qualicoat, in recognition of these developments, has now approved a number of excellent two-coat systems, these can be seen on the approved powder systems list at www.qualicoat.net.
The approved applicator, however, and the approved powder supplier are the parties who offer warranties. Where a location is hazardous, where the coated part is challenging, where a long period warrant is required, a two coat system will help. Two coats provide an additional barrier to the negative weathering effects of UV light, temperature and moisture. A two-coat system can provide superior edge coverage. For these reasons, an applicator who chooses an approved Qualicoat two-coat system may have more confidence in the warranty period to be offered after discussion with their powder supplier.
Two-coat systems over aluminium are gathering traction and have a role to play in the armoury of Qualicoat approvals designed to better tailor the finish quality to the clients’ requirements.
Anodic finishes continue to gain popularity with specifiers for architectural metalwork on new and refurbishment projects. Natural anodised aluminium is a robust, attractive finish, however, coloured anodising (eg, gold, bronze or a blue grey) can be very expensive. Additionally, as anodising is a natural process, it is vulnerable to variation in terms of surface appearance and colour fidelity. In response, powder manufacturers have developed ‘look-a-like’ finishes to anodised colours. These have become very popular as they simulate well the natural reflectance of anodised aluminium and particularly coloured anodised material.
While anodising an aluminium surface offers a natural colour and appearance, which changes with the direction of light and the type of processed aluminium used, it may present colour consistency issues – particularly between extrusions and sheets. The anodic powder coat alternative, by contrast, provides a consistent colour, shade and reflective appearance, making it easier to match sheet and extrusion on site. One other main benefit is that anodic powder coating is not limited to being used on an aluminium substrate as it can be used on other materials substrates such as steel.