In general, there are variety of powders that are used in the process of powder coating and polyester powder coating. However, the two most commonly used types of powders are thermoset powders and thermoplastic powders. Thermoset powders are essentially pre-treated( curing or crosslinking take splace so that once cured, the coating will not remelt). This particular catergy of powder, generally includes epoxies, acrylics and most polyesters. Thermoplastic powders, on the other hand, can be remelted if they are exposed to the appropriate amount of heat. Typical Thermoplastic powders include most vinyl, fluorocarbons, and nylons.
Powder Coating Process
There are three main steps to create industry standard powder coating—pre-treatment or part preparation, application of the appropriate powder and curing. Step one, also known as pre-treatment ensures that any oil, dirt or greases are properly removed before application of the powder. Typically this is done through specific pre-treatment chemicals such as phosphates and chromates. Additionally, some products also required electrocuted before application.
Step two is an application. Generally, the powder application process is accomplished by using an electrostatic gun that sprays the powder onto the metal components. Other application methods or techniques include electrostatic fluidized bed coating and electrostatic magnetic brush coating also known as EMB. The final step in the powder coating process, curing, is when the powder is heated to such a degree that it melts and creates basically a higher molecular weight polymer. Powders cure at 200 degree Celsius.
Kinds of Polyester Powder Coating
This type of powder coating utilizes the general powder coating process. With polyester powders, however, their application is used for protective purposes. In other words, Epoxy Polyester Hybrid powders are used for shelving, power tools, fire extinguishers, hot water heaters and so on. Basically, any indoor product that needs a protective layer can be coated with hybrid powders.
Polyester TGIC powders are another kind of powder that again provides a protective covering, but is used on items with mechanical properties like lawn furniture, air conditioners, aluminum extrusions and automotive wheels. Another commonly used Polyester powder is Polyester Urethane Powder, which has excellent weathering properties. Overall, Polyester powders provide a look and feel similar to nylon coating or coverings, can be applied without the use of a primer and have high-quality exterior durability.
