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Weathering Devices: Let the Sun Shine Down

imagesAbout 75% of the North American coil coating industry is dedicated to building products. Since the lifetime of these products is measured in decades, as opposed to merely years, the weathering performance of the coatings used for this market is critical. Understanding how coatings perform, therefore, is essential. There are many approaches to studying weathering performance, and one of the more interesting techniques to accelerate the weathering process involves the devices described in these two ASTM standards:

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Exploring the Diversity of Coil Lines

ecoverde-1Manufacturers have long benefitted from the speed, precision, and non-polluting aspects of using coil lines to make prepainted metal panels. However, some manufacturers are unaware that coil lines can perform a variety of functions on metal coils, from reclamation to pretreatment to simply giving them a better-looking finish. Here are four ways manufacturers benefit from using coil lines as an effective first-step operation beyond prepainting. Continue reading


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Prepainted Metal: The Hidden Strength, The Visible Beauty, The Functional Capability: Part Two (of Three)

In Part One, we discussed The Hidden Strength of prepainted metal. It’s easy to take for granted all that lies beneath the surface of prepainted metal: the cleaning and pretreatment of the base metal, the metallic coating, and the continuous process that prepares the metal strip for primer and topcoat, all in one pass through the coil coating line. Here in Part Two, we’ll learn about the only feature that is actually visible in a prepainted part—the topcoat; that is, The Visible Beauty. There is, however, more to it than meets the eye. Continue reading


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Prepainted Metal: The Hidden Strength, The Visible Beauty, The Functional Capability

 

Part One (of Three)

Skyscraper in BeijingWhen you look at a piece of prepainted metal, what do you see? Certainly a colorful article that may or may not have some shape to it. Often the metal is fabricated with “ribs” to add structural strength to the panel, or it may be flat, as is the case with a metal composite material (MCM) panel. The surface of the prepainted article might be a smooth, homogeneous surface, or it may have a wood-grained pattern, or it might have a subtle pebbly texture. The color of prepainted metal ranges from whites, grays, and blacks to neutral earth tones to saturated, brilliant colors. Some of the colors have metallic or color-shifting effects. But this layer of color is only what you actually see. What you don’t see is all that is under the surface. Continue reading


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UV Light—Slicing and Dicing the Light That Can’t Be Seen

ultravioletlight2Several years ago, scientists hypothesized that a narrow spectrum of ultraviolet light called far-UVC could kill microbes without damaging healthy tissue. Far-UVC light at about 222 nanometers (nm) has a very limited range and cannot penetrate through the outer dead-cell layer of human skin or the tear layer in the eye, so it’s not a human health hazard. But because viruses and bacteria are much smaller than human cells, far-UVC light can reach their DNA and kill them. In the study, aerosolized H1N1 virus—a common strain of flu virus—was released into a test chamber and exposed to very low doses of 222nm far-UVC light. A control group of aerosolized virus was not exposed to the UVC light. The far-UVC light efficiently inactivated the flu viruses with about the same efficiency as conventional germicidal UV light.[1] Continue reading


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More Than Meets the Eye: Understanding the Long-Term Performance of Prepainted Metal

DSCN4367In NCCA Tool Kit # 26, “Factors Influencing the Long-Term Performance of Prepainted Metal Building,” an emphasis was justifiably placed on the selection of materials. That selection process starts with a substrate that must provide the corrosion-resistant properties for the environment in which the prepainted product will be used, probably for decades. Whether the specifier is considering steel or aluminum, the mechanical properties of the material are of paramount importance. After all, all prepainted metal is post-formed, so the substrate, as well as the paint system, must be able to withstand the rigors of the fabrication process. With a steel substrate, it’s the thickness of the metallic coating layer; with hot-dipped galvanized steel, it’s the zinc; and with Galvalume®, it’s the Zn-Al metallic blend that needs to have an adequate thickness to provide the necessary lifetime and level sacrificial of galvanic properties. There are many parameters to consider. Continue reading


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The Color Project: Part One

Part 1The National Coil Coating Association Technology Committee has been investigating color measurement, color difference, and how best to establish meaningful color tolerances. “Color” is a small word, but one with lots of tentacles. You see a blue car, you call it a blue car. The person you’re walking down the street with also describes this same car as blue. So you both call it “blue.” What’s the big deal? Seeing a “blue” car as it travels down the street is one thing. Putting two metal panels next to each other and comparing their colors closely and carefully is quite another thing. It’s all a matter of perspective. Continue reading