[fn People] “Cut Noise Without PE Foam”... Kim In-gyu Leads Commercialization of High-Performance Color-Coated Steel

[Financial News] “Color-coated steel must evolve beyond products that simply deliver color and design into high-performance materials that solve the inconveniences customers encounter in actual use.”
Kim In-gyu, Color Section Leader at POSCO STEELION’s Product Development Group (pictured), explained on the 15th that this was the direction for developing BalpoSol, a new color-coated steel product for roofing. BalpoSol eliminates the polyethylene (PE) foam previously attached to the underside of roofing materials and incorporates noise-reduction and insulation functions into the steel sheet’s coating layer itself. It reduces impact noise by 5–10 decibels (dB) compared with ordinary steel sheets and was also found compliant in a test for semi-noncombustible materials, he said.
Leader Kim joined the company in 2014 and has been responsible for color-coated steel research and development for 12 years. For this new product, he worked on applying coating technology developed by POSCO Technical Research Laboratories to actual production lines and stabilizing product quality.
To reduce noise and heat transfer, conventional color-coated steel for roofing has had sponge-like PE foam attached to the underside of the steel sheet. However, concerns were raised that the foam could come loose as the adhesive weakened over time, and that it was vulnerable to fire.
Leader Kim said he “asked a fundamental question that went beyond simply improving the adhesive: ‘Could the color-coated steel’s coating itself take the place of the foam?’”
The research team’s solution was to create microscopic air layers in the coating on the underside of the steel sheet. The air layers slow heat transfer and help reduce noise and vibration. Because no separate PE foam is attached, the problem of the foam coming loose can also be avoided.
Leader Kim emphasized that “the biggest differentiator is that, by making the coating layer itself high-performance rather than adding something on, we structurally eliminated delamination (peeling)—the fatal weakness of the conventional attachment method.”
A key challenge in the technology development led by POSCO Technical Research Laboratories and the commercialization process at POSCO STEELION was forming microscopic air layers evenly within the coating. If too few air layers form, noise reduction and insulation performance suffer; if too many form, the coating may become uneven or lose adhesion to the steel sheet.POSCO Technical Research Laboratories therefore developed technology to incorporate a foaming function into a special polymer-resin coating. POSCO STEELION was responsible for applying it to production lines and maintaining consistent coating thickness and quality.
Leader Kim explained, “Confirming the technology’s potential in the laboratory and commercializing it as an actual product were two different challenges,” adding, “The key challenge was to implement the functional coating structure uniformly and reliably on actual production lines and ensure product quality is reproducible.”
The reduction in the number of separate PE foam-attachment steps is also expected to improve production efficiency. It can reduce the use of auxiliary materials and the burden of managing them, as well as maintenance issues caused by foam damage or detachment after installation, he said.
BalpoSol is currently sold primarily for roofing, and its range of applications is being expanded to walls. For overseas markets, the company plans to develop products suited to each country’s climate, building regulations and fire-safety standards, and target existing roofing-material markets.
Leader Kim said, “It is difficult to secure lasting competitiveness through price competition or appearance alone,” adding, “We plan to continue expanding high-value-added markets distinct from commodity products by developing solution-oriented color-coated steel that addresses customers’ usage environments and problems.”

[email protected] Kim Mi-hee Reporter