Imagine driving past a shopping plaza. Its roof has an old-fashioned, rustic appearance - or so you think. As you get closer, you see something new and distinctive about this roof. The color seems to be moving subtly from warm terra cotta to rich copper brown, and finally to vivid tropical green.
New polychromatic roof coatings deliver color in motion, while offering superior protection, durability and energy-saving capabilities that can take architectural projects far into the future.
The Art of Color TravelThe new polychromatic technology is a premium fluoropolymer (PVDF), factory-applied, pearlescent coating system created on the foundation of Kynar® 500 or Hylar® 5000 resin.* These coatings are considered best-in-class and are designed to offer superior durability, color-fastness and gloss retention. They use effect pigments (commonly referred to as “interference pigments”) made from silicon dioxide (SiO2) platelets that are specially coated with metal oxides. These pigment particles create color travel, which allows the coating colors to change subtly depending on the viewing angle and on how light refracts across a particular area (see sidebar). The result is colors in motion, like Mesa Sunrise, which moves from a rich red to blue copper to green gold to gold brown; Serengeti Oasis, which moves from a rich tropical green to terra cotta to copper brown; and Jamaican Reef, which moves from green to slate blue to deep lavender blue.
Primary applications of the new technology include metal roofing and wall panels, aluminum composite parts and accent trim, with possible future end uses such as appliance, interior wall/ceiling systems and extrusion. Additionally, this new formulation adapts easily to classical or modern architectural designs.
High Performance that Keeps Its CoolThe new polychromatic coatings are not only beautiful and visually stimulating, but they also integrate energy-saving technology. They meet the U.S. Green Building Council’s LEED (Leadership in Energy and Environmental Design) guidelines and the U.S. Department of Energy’s Energy Star standards for steep slope cool roofing, while also offering all of the other benefits associated with cool metal roofing (recyclability, fire and wind resistance, energy efficiency, etc.).
The new coatings are based on an existing cool roof coating technology and are expected to exhibit similar performance characteristics over time. In a recent analysis of these cool roof coatings on five-year south Florida panels, several of the formulations tested retained nearly 100% of their initial solar reflectance, thermal emittance, color and gloss. These results translate into excellent product performance and weatherability for years to come.
A Durable, Sustainable SystemSimilar polychromatic coatings have been introduced to the automotive market in the past. The 2001 film Swordfish, starring John Travolta, featured a TVR Tuscan Speed Six that exhibited the spectacular color changes of high-tech paints. It was only a matter of time before chemists developed a suitable formulation for the coil coating market that would offer the required levels of quality and robustness.
In order to commercialize this product for building and construction through coil applications, it was critical to ensure that the technology would apply consistently from batch-to-batch and coil-to-coil to avoid introducing headaches into the supply chain (starting with the coater and ending with the roofing contractor). A partnership between the coating formulator and a custom coater was deemed necessary to help work the “kinks” out of the technology, determine the optimal formulation and fully understand its application characteristics.
Precoat Metals, Inc. of St. Louis, MO, a toll coater with heavy participation in the building products arena, showed keen interest in the technology and agreed to work with BASF Industrial Coatings Solutions on this effort. Precoat and BASF worked together, sharing information, costs and other details, until each party was comfortable that a high-quality, consistent product could be introduced to the marketplace. Their licensing agreement gives Precoat exclusive rights to the technology through 2008. In 2009, the technology will be available on a broader scale.
Architects, aluminum composite manufacturers and building owners are seeking new ways to make a unique statement aesthetically, as well as to fulfill industry regulations associated with sustainable construction. New technologies such as energy-saving polychromatic coil coatings can help them achieve these goals.
For more information, visit www.basf.com/usa. Precoat Metals, Inc.’s website is at www.precoat.com.
*Kynar 500 is a registered trademark of Arkema, Inc., and Hylar 5000 is a registered trademark of Solvay Solexis.