Polymer Shutters

Shutter manufacturers have traditionally favoured high VOC paint technologies over the years, such as petroleum-based polyurethanes and nitrocellulose acrylics. More so polyurethane (Two-pack) because of its inherent strength, versatility, and low cost. The high level of solvent in these traditional paint technologies allows the paint to cure very quickly, which is a major advantage for high volume factories for output reasons.

Governments around the world however, are making changes to their laws for VOC’s due to the associated health and safety risks, with countries such as Sweden, and some U.S states all but banning solvent based systems and changing to waterborne technologies in manufacturing. Even China is considering mandating a change away from the current use of high VOC based paints.

So what are VOCs?

Volatile Organic Compounds have a high enough vapor pressure at ordinary room temperature to significantly vaporise and enter the atmosphere. The accidental release of VOCs into the environment can damage soil and groundwater, however it is the vapours that escape into the air through the application and drying of paint that pose the greatest risk of short-term and long-term adverse health effects, and that’s not even considering the flammability factor. Concentrations of many VOCs are up to ten times higher indoors than outdoors.

Conventional paint technologies have around an 84% VOC solvent content and 16% solids, whilst a typical waterborne paint system has around 70% water, 20% solids and only 10% solvent. By using a waterborne paint with low VOCs, the quality of the air indoors becomes safer for those who live or work inside.

PROS OF WATERBORNE PAINT

Non-toxic
Environmentally friendly
Reduced air emissions
Coatings have hardness and flexibility
High heat reflectance
Excellent colour retention
No additives, no thinners, no hardeners
Low flammability
Provides excellent adhesion

CONS OF WATERBORNE PAINT

More expensive equipment required
Stainless steel or corrosion resistant applicators
Longer curing time than traditional paint systems
Specialised drying equipment required
More sensitive to temperature and humidity in application

BUYING WATERBORNE SHUTTERS – WHAT TO ASK

Decision made, you’re going to invest in waterborne painted shutters. Clearly the cons relate to the application of the paint in manufacturing so you don’t need to consider that when choosing a retailer to buy from right? Waterborne painted shutters are all the same aren’t they?

No, they’re not.

Waterborne paint has a different viscosity to traditional solvent-borne paints, it handles, tints and sprays differently. Dry, low humidity in the air can result in the paint drying too quickly throughout application process. This is a particularly important consideration if the paint is being applied by hand with a spray gun.

Many small to medium factories who assemble shutters made from wood, polymer (PVC) and aluminium, don’t have the set up to extrude all these materials from virgin product themselves. They purchase pre-painted profile and components from an extruder and they cut and assemble shutters from this. Neither do they have the expensive paint system set-up to effectively repair damaged surfaces to the same quality of finish as the extruder.

Factories this size will touch up damages by hand with a spray gun. As the waterborne paint can dry quickly on application, applying by hand this way will result in some areas of the shutter more rough to the touch than others, and not of the same high quality finish as the rest of the panel. This is due to the waterborne paint drying before it hits the substrate. The rough feel is tiny particles of paint that dried before it hit the substrate.

Most large-scale factories have invested in paint machines and installed spray booths with heated curing rooms and air movement devices to increase production by reducing curing time. Water is corrosive to a variety of metals so these factories use stainless steel pressure tanks, and high quality applicator nozzles on paint machines. Machine application guarantees the exact same distance and speed consistently throughout the paint process so the paint finish is consistent and of the highest quality. These factories not only assemble shutters, they extrude from raw material so they control the supply chain and the quality in all areas of fabrication, unlike the mid size operators mentioned above.