Powder coating is an advanced method of applying a decorative and protective finish to a wide range of materials and products that are used by both industries and consumers. The powder used for the process is a mixture of finely ground particles of pigment and resin, which is sprayed onto a surface to be coated. The charged powder particles adhere to the electrically grounded surfaces until heated and fused into a smooth coating in a curing oven. The result is a uniform, durable, high-quality, and attractive finish.
Powder coatings began to emerge onto the commercial market during the in 1950's (although some research establishments had used the technique in the 1940’s).Early coating was conducted by manually throwing powder onto preheated items from a shallow tray of finely ground polymer (low density polythene). A German engineer, Irwin Gemmer, of the Knapsack-Griesheim AG Company, patented the fluidised bed for powder coating, in 1954. This lead to an expansion of the newly born "powder coating" technique of surface coating. Until this point, only liquid paints or hot "pour-ons" (bitumens) had been used.
From an environment point of view, powder coatings are the best choice for Industrial Coatings applications. Typically, powder coatings are only used in specific coating segment due to limitations related to the Powder Coating Process Technology, (Fluidized bed, Electrostatic spray, Flock or Hot spray, Minicoat, Pipe coating ). But new developments of the inherent limitations of conventional powder coating technology will be uplifted to a substantial extent. Consequently, it will be possible to apply powder coatings, on broad scale, in additional coating segments.
The problematic in metal surface finishing industry is considerably helped by powder coating systems that comply with many performances linked to a competitive cost.
Toughness of a powder coating is the result of a combination of characteristics, such as:
-Corrosion protection,
-Outdoor weathering lasting,
-Chemical resistance to environment of miscellaneous industries, -Hydrocarbons, solvents, organic acids, inorganic salts and alkalis.
-Surface finishing resistant to cleaning agent,
-Extreme stress while staying intact and remaining with good adhesion,
-Requirement of flexibility,
-Impact resistance,
-Abrasion resistance,
-Low coefficient of friction,
-Natural and various colors available,
-Protective barrier to sea atmosphere,
-Environmental low VOC coating,
-Approvals for contact with foodstuff and drinking water,
-Thermal resistance,
-Vibration absorbing capacity,
-Electrical insulation properties.
