In Part One, we discussed The Hidden Strength of a prepainted metal system (the base metal, the metallic layer, the pretreatment and primer). In Part Two, we examined The Visible Beauty of prepainted metal: color, gloss, texture. Strength and beauty—not to mention durability and sustainability—are important features, but the coil-coating industry also offers The Functional Capability that sets prepainted metal apart from other products, and most of this functionality can be built into the coil-coated topcoat. This topcoat layer, compared to the base metal, is thin—about 2% to 4% of the total thickness of the prepainted article. But what an incredible layer it is! In addition to providing the aesthetic properties (color, gloss, texture, etc.), coil-coating topcoats can be formulated to provide many functional properties. Continue reading
By Kelvin Russell, Precoat Metals
Chances are, if you’re reading this blog regularly, you already know that prepainted metal is the substrate of choice for metal buildings, HVAC products, appliance products, and more. The list of applications for prepainted metal is endless, as are the reasons why prepainted metal is the substrate of choice for so many products. To be honest, this long list of reasons is not the subject of today’s post, save one: aesthetics. So many beautiful colors! Color and texture can make blockbusters out of the ordinary products we take for granted. In addition to the performance benefits of prepainted metal, its almost limitless beauty is quickly rising to the top of the list of reasons why consumers choose it for any number of applications. But then tradition steps in and says, “You can’t use metal here, it has to be wood!” Well, phooey. Now what? Continue reading
In the last post, Part One, we left off with two facts: We depend on a numerical description of color and color difference rather than judging a sample vs. a standard visually; and NCCA began to investigate ΔE2000 to determine how well it might work in the coil industry.
Let’s start Part Two with a short discussion on ΔE2000. It is way more than the usual ΔE with a little “2000” as a subscript. (If only it were that easy.) Our current ΔE is a straightforward root-mean-squared calculation, as shown here:
ΔEHunter = [(L2-L1)2 + (a2-a1)2 + (b2-b1)2]1/2
The 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
Whatever happened to UV-EB (ultraviolet-electron beam) cured coatings technology? The simple answer is, “Still there. Doing just fine.” For the coil coating industry, the answer is even simpler: Never left the starting block, even though a great deal of effort went into the development of UV-EB coating technology suitable for the coil-coated building products industry. I’ll get to those developments in a bit, but first, a little history.
You may think that that standards development in ASTM is a slow process—as it tends to be in most associations with volunteers. You may think ASTM-ers talk endlessly about the stickiness of tape or the problem with the precision of the pencil hardness test. Yes, there is plenty of that. There is also the development of new standards when new technology becomes established.
Anyone developing a piece of testing equipment in the paints and coatings industry—or the medical industry or the building and construction industry—can see the value of having an ASTM standard available to clarify its use and to describe its precision. While all of these things are important, I have found that ASTM is also the one association where science can “happen” most readily. Hard to believe? Read on! Continue reading