Powder coating is making a major impact in the finishing industry. By utilizing the natural principle that opposites attract, this finishing technology offers manufacturers increased economic benefits and superior quality.

Powder coating has been referred to as a "dry painting process." But to manufacturers, who have been using it for more than a decade in place of liquid paint, it is like the difference between a Model T and a Mercedes Benz. That's because powder coating is a modern technology. For the first time, end-use manufacturers are able to engineer their finishing operations to a degree only dreamed of heretofore, while eliminating many of the problems that have been traditional in the finishing operation.

A full palette of colors awaits them to serve any market. An almost infinite range of properties are theirs to choose from, including resistance to ultra-violet rays, greater durability, better corrosion resistance plus any of a dozen other properties, depending on the particular needs of the user. Each can be accomplished by control of the powder formulation or finishing process.

The process is simple in concept and operation. Dry powder is pneumatically fed from a supply reservoir to a spray gun where a low amperage, high voltage charge is imparted to the powder particles. The powder used in the powder coating process is comprised of resins and pigments and in its dry, formulated state is then sprayed onto a part to be finished. The parts to be coated are electrically grounded so that the charged particles projected at them are firmly attracted to the part's surfaces and held there until melted and fused into a smooth coating in the baking ovens.

The coating process can be done manually or it can be a highly sophisticated automatic operation, where computer programmed robots can perform the spraying in booths up to and over a hundred feet long. The wide variety of equipment available makes powder coating feasible for the small end-use manufacturer, as well as for the very large user who may require an extensive finishing operation for multiple products.

Because the powder is dry when sprayed, any overspray can be readily retrieved and recycled regardless of whether the finishing system is manual or highly automated. Several methods are available depending on the application equipment in use and the size of the finishing operation. All however operate on the same principle: the unused powder is separated from the air stream by various vacuum and filtering methods and returned to a feed hopper for reuse enabling efficiency-use rates to approach almost 100 percent.

While material and equipment costs are similar to liquid finishing systems, savings can be achieved in energy, labor, production, waste disposal, and meeting EPA standards, making the real, bottom line costs of powder coating systems less than liquid finishing systems.

• Energy--Because venting of fumes from wet spray paint solvent systems is not necessary, the need for air makeup--and the high costs for heating the air in colder climates--is lessened, resulting in considerable energy savings.

• Labor--Labor costs are often substantially lower in plants using powder coating because automatic systems require less manpower and worker environment is more favorable-plus faster clean-up time and fewer clothing problems.

• Efficiency--Because no drying or flash off time is required and the powder coating application process permits parts to be racked closer together on a conveyer, more parts can speed through the production line resulting in greater operating efficiency and lower unit costs. Despite the increase line speed, the reject rate is normally significantly lower when using a powder coating system than when a wet solvent system is utilized.

• Waste Disposal--With a dry powder coating system, there is no liquid paint sludge to haul away to a burial site. That means more dollar savings and a major reduction of an increasingly difficult disposal problem.

• Pollution--Air and water pollution problems are virtually eliminated with a powder coating system, which in turn, reduces the high costs of anti-pollution equipment and the time and money spent in dealing with federal and state regulatory agencies.

Powder coatings are used on an increasing variety of products and components. Industries with multiple applications include appliance; automotive; electrical; medical and office furniture; building and architectural; farm, garden and industrial machinery; fabricated products and miscellaneous products.