Electrostatic painting, also known as “powder coating,” uses the principal of “opposites attract” to create a uniform and durable finish on metal and some plastics without the sags, runs, drips and bubbles which can occur with traditional liquid paints. It’s used on many plastics and every kind of metal.
Electrostatic painting process is simple in concept and operation. Dry powder comprised of resins and pigments is pneumatically fed from a supply reservoir to a spray gun where a low amperage, high voltage charge is imparted to the powder. The part to be finished is electrically grounded. When sprayed, the charged powder articles are firmly attracted to the grounded part’s surface and held there until melted and fused into a smooth coating in the curing ovens.
It’s much more durable than liquid paint and it’s an environmentally friendly process because there are no solvents to evaporate into the air or go down the drain.
Different formulations (epoxy, urethane, polyester or a hybrid) are determined by the intended use of the item. For example, urethane and polyester offer the best exterior durability while epoxy is best for corrosion protection and chemical and solvent resistance.
A range of literally thousands of color glosses, metallics and antique effects are available and local companies offers hundreds of “stock” colors all for same price.
Consumers may also look through sample books and pick other colors to be ordered from the manufacturer at an additional cost (Powders must be mixed at the factory, you can’t mix two together or stir in a pigment as with liquid paint.)
It is also possible to have something matched perfectly by sending to the manufacturer for computer analysis. Computerized matching requires extra time and adds a considerably higher extra service charge, as well. (A builder might need metal doors to match anodized window frames perfectly).
Because the surface of parts must be free of oil, dirt and rust prior to powder-coating, companies offer sandblasting, chemical and acid pre-treatments.
The customary turn-around tiime is 7-10 days, and often job can be done sooner for an extra “rush” fee.