Powder coat is a solvent free coating system using thermoset (requiring heat), solid particles of powder coat that are applied using electrostatic guns and then baked in an oven to melt, flow and cure the powder.
Powder is comprised of several components;
The resin, this is the body of the powder coat and powder is available in a number of resin systems. The most common is polyester powder, this has good exterior performance (U.V. stable), is abrasion resistant, resists mild chemicals and is hard wearing.
Other resin systems in common use epoxy powders, which are highly resistant to chemical attack, but have poor U.V. resistance making it unsuitable for external applications. A common application for this type of powder is Fusion Bonded Epoxy (FBE) were the powder is applied to very high film builds (300um+) and is used to coat heavy duty water valves. Epoxy powders are also used in powder primers to add durability to the coating system.
Polyurethane powder is U.V. stable, chemically resistant and abrasion resistant, it is generally used as an anti-graffiti coating for public infrastructure and public transport applications.
Fluoropolymer powder uses a highly U.V. stable resin system and colour pigments that resists colour change and fading in exterior applications. It is used to coat architectural aluminium for windows and facades and major infrastructure projects and can carry a performance warranty of 25 years.
Hybrid powders are made using a mixture of resin systems, the most common of which is polyester and epoxy, this utilises the benefits of both systems to produce a quality powder for general industrial use.
Pigments provide the colour for the powder and the colours can matched to any standard colour range and custom made colours.
Matting agents are added to the powder to lower the gloss level and produce satin (approximately 60% gloss) and matt finishes (approximately 30% gloss).
Various additives can be mixed into the powder to create textured, ripples and metallic finishes.
The flexibility of powder coating technology can produce a powder coat for just about any coating application. The major powder suppliers stock a varied range of colours and powder types and can also custom match colours and finishes to meet the needs of the market place.