Coil Coatings Manufacturers Overcome Challenges with Energy Curing

Energy curing technology offers a lot of benefits for users, including environmental and production advantages. But as is the case with virtually any new technology, there is usually resistance to the new process, as the older technology is entrenched.

For UV/EB coil coatings manufacturers, there is the knowledge that energy curing would benefit the coil customers. The trick is getting the coil manufdactuers to give UV and EB a try. The good news is that there are coil companies successfully using energy curing, and their competitors are taking notice.

Beckers Group CTO Gavin Bown notes that Beckers has successfully commercialized RUV3 and RUV4 topcoat systems, but there is a long road ahead.

“We are still at a relatively early stage in the journey to make UV/EB coil coatings a full replacement for the current solvent-borne technology,” Bown says. “We have a clear roadmap to get there.”

One key is to leverage strategic partnerships with customers, equipment suppliers, raw material suppliers and universities for fundamental research.

“In particular, we need to develop a full understanding of three key dimensions: substrate adhesion, durability and flexibility,” Bown observes. “One of the main challenges has been adapting the technology for non-porous substrates like steel and aluminum, which require flexible paint so the panels can be formed after the coating. We ensure that our formulations provide the necessary flexibility for post-coating forming processes without compromising hardness. This called for extensive R&D and close collaboration with suppliers and customers to adapt both the coatings and the application equipment.

“Ensuring that UV/EB coatings match the durability, corrosion resistance, and aesthetic qualities of traditional solvent-based coatings is critical, too,” he adds. “Here, Beckers focused on developing formulations that met industry standards, such as RUV3 and RUV4, for medium to high UV/EB resistance.”

Bown points out that transitioning UV/EB technology from lab-scale to full industrial application poses significant challenges.

“We are partnering with customers to retrofit existing coil coating lines, ensuring that the new technology meets high-speed production requirements while maintaining performance standards,” says Bown. “Transitioning customers to UV/EB curing technology needs training and support. Beckers provides comprehensive training programs, detailed technical documentation, and on-site assistance to help customers seamlessly integrate UV/EB curing into their production lines.”


Christopher Bradford, market director for AkzoNobel’s Coil & Packaging segments, notes that the use of pigmented and opaque systems can limit the penetration of UV light, affecting the depth and efficiency of the cure in coil coating applications.

“Surface-level challenges, such as oxygen inhibition, also need to be addressed,” Bradford adds. “We’ve tackled these issues through a strategic selection of UV sources and curing parameters, careful formulation using optimized resins, pigments, and additives, and, when needed, a secondary EB curing step. These measures help ensure consistent and thorough crosslinking across all layers.

“Conversely, the introduction of UV and more widely energy cure will allow to tackle very differently greenfield line projects by a paradigm change in the design of the future line, starting with re-thinking space requirements and utilization, investments and operation processes,” Bradford concludes.

Craig Smith, PPG global technical segment director, Coil and Extrusion, points out that the fact that all materials in these coatings become part of the final film presents some challenges not faced with thermally cured coatings.

“No longer can we easily add solvents to adjust the viscosity and application properties without changing the properties of the coating,” Smith observes. “Having detailed knowledge of the customer’s process when formulating the coatings is important to avoid the need for adjustments during application, although controlling the coating temperature can be a useful tool for fine-tuning application without impacting coating properties.”

Kurt Bowen, global portfolio director for Sherwin-Williams Coil Coatings, said that using radiation cure coil coatings can present several challenges.

“One issue is the higher viscosity of 100% solids coatings, which can affect appearance at higher line speeds,” he noteds. “Care must be taken while formulating to optimize viscosity for both application and appearance, and to not sacrifice other performance parameters.  Resin weathering performance is also improving.  We are utilizing our development groups across Sherwin-Williams to make gains in these areas. To make a successful product, the coating formulation, equipment and application parameters all must work together seamlessly.”