Pre-assembled Parts and Components
Pre-assembled parts were the first products finished with UV-cured powder coatings. These were a fully assembled and harnessed electric motor and a radiator sub-assembly for a light duty truck. Each of these products contained a variety of heat-sensitive materials that were not damaged in the UV-cured powder coating finishing process, maintaining the quality and integrity of the finished product. Typically, heat sensitive elements and materials will degrade or deform when exposed to heat. Once damaged, they make the finished product unusable. These may be plastics, rubber seals, electronic components, gaskets or lubricating oils. The component parts that require finishing are normally finished as sub-assemblies or pieces and parts. Often, this finishing is costly and sub-optimal in regard to the final product need or use and is often more decorative than functional. Because UV-cured powder coating is very fast and uses a minimal amount of heat, it is possible to build a fully assembled product and finish it without damaging the internal components. To fully exploit the benefits of UV-cured powder coating of assembled products, it is necessary to change traditional thinking of manufacturing and assembly and evaluate its cost and time advantages in a total product cost model.

Sustainable
Manufacturers and service providers not only are challenged by the demand for innovative products and services, but are being further challenged to assure sustainability up and down the supply chain. Customers make intentional and conscious buying decisions based upon criteria and standards that define products and services as “sustainable.” Consumers are actively seeking materials and processes that are safe – safe to make, safe to use and safe to dispose. UV-cured powder coatings meet all three of these “safe” requirements. They do not contain solvents, VOCs or HAPs (hazardous air pollutants) and are non- toxic. Manufacturing and use of UV-cured powder coatings do not require any permits, special air handling, operator breathing devices or flammability restrictions or controls. UV-cured powder coating has the smallest carbon footprint of any commercially used coating material2. These results are from third party evaluation and testing of various types of industrial coating materials. A safe and low-risk work environment lowers insurance and operating costs.

Figure 2: Finishing Technology Time Analysis by Process Step

The application and handling of powder coatings are safe and easy-to-use. Depending on the type of application system, color changes can be manually accomplished in minutes or instantly with automatic equipment. Material handling and cleanup are very simple and easy. A spill can be swept up or vacuumed with no residual damage to equipment or property. Again, depending upon the type and complexity of the application system, powder can be manually or automatically sprayed. A major benefit of powder coatings is the ability to re-capture sprayed powder coating material and re-introduce it into the finishing operation. Using a reclaim application system, it is possible to achieve transfer rates of greater than 90 percent. Residual powder can be recycled into a manufacturing stream. The EPA considers powder coatings a “Pollution Prevention” coating technology3. UV-cured powder coating reduces or eliminates the various and numerous material handling, permitting, environmental and waste disposal costs associated with the use of liquid coatings – regardless of type of coating, whether solvent-borne, low VOC, waterborne or UV liquid.

Lean Manufacturing
Companies are using lean manufacturing principles to eliminate unnecessary costs and increase profitability. UV-cured powder coating and application technology meets all the criteria of lean manufacturing. The focus of lean manufacturing is to provide value-add processes with less work through the elimination of waste. The Part Cycle Time Analysis in Figure 2 (on page 16) identifies and measures the process steps of UV-cured powder coating, thermoset powder coating and liquid coating. The chart clearly and explicitly demonstrates the lean advantage of UV-cured powder coating compared to the other two materials and processes. The material application time for each is comparable; however, the total time to produce a finished product using UV-cured powder coating is significantly faster. This time advantage has cost and economic benefits that may not be readily apparent. A UV-cured powder system can produce more material in a given period of time; increasing operating capacity, reducing WIP inventory, lowering the cost of quality, using less energy per part produced and increasing cash flow. UV powder coatings clearly demonstrate the lean attributes through adding value and reducing wasteful time and energy in the finishing process.

An additional benefit and cost advantage of a UV powder application system is its compact size and small plant footprint. A UV-cured powder application system has a typical footprint of 2,000 sq. ft. A comparable thermal liquid finishing system has a footprint of 16,000 sq. ft. Assuming a net cost of $7.50 per square foot for factory space, the cost savings of a UV-cured powder coating system is $105,000 per year.

Conclusion
The demand for innovative and sustainable products and services will continue to grow, and market opportunities for UV-cured powder coatings on various substrates and assembled products will continue to develop. Adoption of UV-cured powder coatings will be accelerated by new developments in chemistries that expand the durability and performance of these coatings. Use on plastics and composites will increase as newly developed plastics and composites are brought into the market. UV-cured powder coatings can cost-effectively finish these materials and add greater market value. UV-cured powder coatings have unique and inherently sustainable features not found in other finishing materials. Their significant and compelling lean manufacturing attributes are part of the reason UV-cured powder coatings and application technology is gaining in popularity. There is an exciting and profitable future for UV-cured powder coatings used to finish heat sensitive substrates and assembled products.

References
1) Moens, Luc, Erwin Bauters, and Marc Van Muylder, Cytec Industries. “Powder Coating Resins for Outdoor Applications.” Asia Pacific Coatings Journal (April May 2011): 12-13. Print.

2) Morris, Dave, and Jos Verlaak. “Life Cycle Assessment for Industrial Coatings Applied on MDF.” The Decorative Surfaces Conference. Fairmont Turnberry Isle Hotel, Miami, FL. 2 Nov. 2011. Technical Conference.

3) “Pollution Prevention in Painting and Coating Operations.” Pollution Prevention in Painting and Coating Operations. Ohio EPA, Sept. 1994. Web. 06 July 2012. http://web.epa.state.oh.us/opp/paints/fact23.html.

Michael Knoblauch is the president of Keyland Polymer Ltd., and Ryan Schwarb is the company’s formulation and production manager. For more information, call 216.741.7915 or visit www.keylandpolymer.com.