The Next Leap Forward in Edge Protection

The Next Leap Forward in Edge Protection

By Shelley Verdun

For metal goods manufacturers, powerful corrosion protection is not only essential for asset life and reliability, but also a strategic advantage that strengthens brand credibility and elevates competitive standing.

In metal manufacturing, sharp edges are the Achilles’ heel of corrosion protection. The rheology of traditional powder and liquid coatings causes them to thin and pull back from edges during curing, leaving them more vulnerable to salt, chemicals, pollutants and moisture. The result is predictable: premature corrosion, reduced reliability and higher maintenance costs. The reason is physics.

The Path of Least Resistance

Traditional powder coatings struggle to cover corners, grooves, weld seams and edges because electrostatic forces drive powder toward the easiest to reach areas. As a result, powder builds on open areas while pulling back from recesses or tight spots. This phenomenon, known as the Faraday cage effect, leads to thin, inconsistent coverage on critical edges and corners.

Powder formulations claiming high-edge protection have been around for decades, but their performance only offered incremental gains. Suboptimal melt flow, uneven leveling, inconsistent particle size distribution and weak film build led to insufficient and unreliable edge coverage.

In 2019, PPG introduced a high-edge powder coating built on proprietary resins systems. This technology solved the persistent challenges inherent in high-edge powder coatings by delivering consistent, complete coverage, even on complex geometries.

With the product, manufacturers could protect laser-cut edges and intricate shapes such as mesh, louvers and blades in a single coat. These were applications where standard industrial coatings and earlier high-edge powders often failed.

Smoother Finishes Without Compromise

While contemporary high-edge powder coatings delivered one-coat corrosion resistance, their most notable drawback was that they commonly produced an orange peel texture finish.

Building on the first-generation's success, PPG launched ENVIROCRON® Extreme Protection Edge Plus powder coating in late 2025 combines edge corrosion resistance with a sleek, smooth finish. By consistently achieving appearance levels beyond the Powder Coating Institute’s Visual Smoothness Standard of six, this innovation bridges the gap between performance and aesthetics.

Like its predecessor, this versatile solution works with both manual and automated coating systems and is compatible with multiple powder chemistries, including polyesters, low-cure polyesters, polyurethanes and polyester-epoxy hybrids.

“Manufacturers can adopt these solutions without major disruptions by building on their existing powder coating systems and equipment,” explains Kathryn Shaffer, PPG powder global technology platform manager, Industrial Coatings. “This compatibility helps ease hesitancy among risk-averse manufacturers considering new technologies.”

Overcoming Barriers to Mainstream Adoption

Despite clear benefits such as reduced warranty claims, longer product life, lower maintenance costs, shorter production cycles and diminished need for mechanical edge rounding, high-edge powder coatings have yet to reach mainstream use. Lack of awareness is one barrier because contemporary versions are only about six years old, and many manufacturers are still learning the technology’s capabilities.

Familiarity is another challenge. Many manufacturers have historically used a two-coat process to build film thickness. But traditional formulations still pull away from edges, leaving those areas vulnerable to the development of corrosion in the field.

PPG’s one-coat ultra-durable polyester powder has demonstrated edge protection and corrosion resistance comparable to competing primer-plus-topcoat systems. Despite potential efficiency, efficacy and cost saving gains, shifting from long-standing two-coat processes takes time, even when the benefits of change are impressive.

For manufacturers committed to their tried-and-true two-coat systems based on specification, incorporating a high-edge primer with an ultra-durable high edge polyester powder topcoat can significantly enhance edge corrosion protection without disrupting existing workflows.

With growing awareness, proven field results and compatibility with existing equipment, high-edge powder coatings are poised to become a defining advancement in modern metal finishing.

Shelley Verdun is business manager, powder coatings, Industrial Coatings at PPG.