To successfully apply a spray paint coating solution that works, it is necessary to understand ‘the chemistry of surface coating technology’.
At ORS we don’t just spray paint things, we understand what we are applying, and we understand the substrate (the surface beneath the coating) we are applying the paint to. This means we achieve good adhesion between the substrate and our coating system ensuring long lasting performance.
The surfaces we paint include:
- Polyester powder coated and anodised aluminium sections, rainscreen cladding and sheet fabrications
- Zinc coated or galvanised steel
- Plastisol coated steel cladding, sheeting and fabrications
- Polyvinylidene fluoride (PVDF) coating cladding, extruded aluminium and cast aluminium
The reasons for re-coating include; updating the decorative appearance/re-branding, dilapidations, maintenance and refurbishment.
Most factory applied architectural finishes have a life expectancy of between ten and twenty five years. Warrantees attached to most of these systems usually require that the buildings are cleaned every year, as this rarely happens the warrantees are usually not honoured.
As the coatings age, degradation may manifest itself in several ways; corrosion, red rust or iron oxide, aluminium and zinc corrosion (sometimes called white rust), filiform corrosion, UV degradation, chalking, thinning, embrittlement, loss of adhesion and de-lamination.
Corroded metals require removal of all corrosion followed by chemical neutralisation of the oxides prior to priming and finish spraying.
Ultra violet (UV) light degradation is displayed as a faded finish and has a patchy white chalky appearance. Some colours are more susceptible to chalking than others, the quality of the pigments used in the formulation of the paint is critical to its resistance to chalking. Paints also include binders, extenders, matting agents, solvents and many more chemicals. The formulations determine the long term performance of the finished product.
The paints we use have different properties designed to meet particular needs. For instance, ceiling coatings are designed to cover stains and oils easily but are not suitable for exterior applications.
Exterior quality paints suitable for spraying include; single pack alkyds, acrylics usually cure via solvent evaporation. Two component epoxy’s, acrylics, plyurethanes etc. are cured by adding a catalyst or hardener. This creates an irreversible chemical reaction brought about by the linking of one polymer chain to another. The new paint compound brought about by these changes is tough, resilient with excellent adhesion and provides long term performance. Moisture cured paint systems go through a similar change. The paint is sprayed onto the surface and the natural humidity in the atmosphere causes a change which brings about the curing of the paint film.
The latest high solids paint mean ‘less solvents’, combined with the use of high volume low pressure (HVLP) spray application technology dramatically reduces the release of volatile organic compounds (VOC’s) into the atmosphere. This means our clients get high performance coatings with minimal impact on the environment.
Only a few years ago, water based paints designed to replace solvent based paints could only be applied in very carefully controlled spray booths. These paints were very sensitive to temperature, humidity, airflow and air cleanliness meaning that they could not be applied on site. Today, new generation water based paint systems which are more tolerant to variable application conditions are being developed and will be capable of being applied on site and provide the kind of performance previously only achieved by solvent based paints systems, whilst reducing even further the impact on the environment.
ORS are passionate about developing new techniques with all suppliers, which is why we have no direct affiliation with any one manufacturer. We do however have close associations with those who share our commitment to quality, the environment and new techniques. These include; Akzo Nobel, Cromadex, HMG, Lechler, PPG, Trimite and Zinsser Coatings.