Powder coating is a type of coating that is applied as a free-flowing, dry powder. The main difference between a conventional liquid paint and a powder coating is that the powder coating does not require a solvent to keep the binder and filler parts in a liquid suspension form. The coating is applied electrostatically and is then cured under heat to allow it to flow and form a “skin”. Powder coating creates a hard finish that is tougher than conventional paint.
Powder coating is mainly used for coating of metals, such as household appliances, aluminium extrusions, drum hardware and automobile and bicycle parts.
Advantages of powder coating instead of other coatings
- Powder coatings contain no solvents and release little or no amount of Volatile Organic Compounds (VOC) into the atmosphere. Thus, there is no longer a need for finishers to buy costly pollution control equipment. Companies can comply more easily and economically with the regulations of the Australian Government.
- Powder coatings can produce much thicker coatings than conventional liquid coatings without running or sagging.
- Powder coated items generally have fewer appearance differences between horizontally coated surfaces and vertically coated surfaces than liquid coated items.
- The wide range of speciality effects are easily accomplished using powder coatings that would be impossible to achieve with other coating processes.
- Curing time is significantly faster with powder coating as compared to liquid coating.
The powder coating process involves three basic steps:
- Part preparation or the pre-treatment
- The powder application