Above: The Fluropon Continuum is designed primarily for building façades that require durability and a clean, bright aesthetic.

Proven mica-based formulas let coaters extend product warranties, save material and time, and even expand capacity

July 2021 - Commercial and residential building developers and architects don’t want their projects to start looking shabby after a couple decades due to weathering or other environmental factors. When they wish to clad buildings in coated metal panels or specify metal roofing and trim, they want a material that will look almost new for a very long time.

Metalescent coil and extrusion coating systems have long been specified for their classic aesthetics and lasting performance. Three-coat 70% PVDF metallic systems are widely accepted as the industry standard among builders and architects who want to make a lasting impression.

Over the last 30-plus years, Sherwin-Williams has tested thousands of metalescent coating formulations on natural outdoor exposure to develop its new coating system with enhanced performance and expanded aesthetic options, but it uses only two coats rather than three. The product, just introduced to the market this year, is Fluropon Continuum 70% PVDF Coating System.

Channing C. Beaudry, global technical director for Sherwin-Williams Coil Coating, says the Continuum product line took many years of steady research to prove its worth.

“This is a PVDF coating with a proven track record of durability. The data we gathered over decades looked at different raw materials within [our basic] formulation. People expect us to move quickly and they may believe that chemists have an aha moment, but that’s far from the truth,” Beaudry says. Instead, chemists study massive amounts of data and follow trends over time. “We put a lot of panels out and tested them and watched what works and what doesn’t.”

Sherwin-Williams has over 150,000 panels at its testing sites at any given time. Some Fluropon panels were placed out there in the 1960s.

Regarding the chemistry for Continuum, he says, “We started some of this testing 20 years ago and put it out without a clear coat, expecting it would fade faster, and we would be able to see that. So we did a bunch of those studies and, after 20 years went by, we found that this one product would not fade. Others failed,” but the Continuum formulas “went on looking better than those with the clear coat on.

“So we donated resources to a more formal study focused on just those. And we found a significantly better performance even though that wasn’t the intent of the original study,” Beaudry says.

Testing conditions

Sherwin-Williams owns land in Fort Meyers and Daytona Beach, Florida. The company built racks, angled 45 degrees to face the sun, and leaves the panels outdoors for years to see how the coatings react. Chemists collect the data and report their findings internally.

“We have over 150,000 panels at the testing sites at any given time. We have Fluropon panels out there that were placed in the 1960s. They still look good and have good integrity,” Beaudry says.

“Whenever we look at new raw materials or new pigments, customers do a production run and send us coated panels to test. We have quarterly visits, continue to look at all our studies, and the team reports which products are performing, and which are not."

There are many tests that go faster, like salt spray and other cyclical tests—wet, dry, wet dry—simulating real-world conditions. But that’s only a portion of the environment. There is also sun and wind. “Natural weathering takes a long time but the data is more valuable,” he says.

2 coats versus 3

In a white paper, the company laid out data showing a similar pewter color in a three-coat  and two-coat formulation and the results of the weathering process. The Fluropon Continuum showed better gloss retention and about the same fade as the traditional three-coat system, even though it had been been weathering nearly a year longer.

In that example, the two-coat system retained more gloss than the three-coat system.

“This goes beyond the cost savings,” Beaudry says of the implications. “There is less material used. In most coating operations, you can apply two coatings in one pass. The applicator must then run the coil through the line a second time for the clear coat.” Without that step, “there is more control. Less is more. You are taking out a variable.

“If you run a coating line, you can double your capacity in some cases. For every ton of metal you coat, you don’t have to put it through twice. You can move on to the next job. We did work with applicators and coaters, and we saw this as helping their productivity.

The same is true for extruders,” he says.

Façade

The Fluropon Continuum is designed primarily for building façades “where you want the durability and the aesthetic look for the long term,” Beaudry says. The Continuum also creates a wider color space. Most people think of mica as having a silver tint. With our effects, it is not just silver and gray. We want to expand the color, get a more vibrant and sometimes sparkly effect. It’s reflective color that you can structure buildings around.”

As the product launches, Sherwin-Williams is working with architects to sample and develop colors. “They work with our laboratories directly. Over the years, as we learned new formulations that worked well, they went up into buildings, but it wasn’t this exact same set of raw materials. There is a tremendous amount of interest in the latest formulation,” Beaudry notes.

Database

Fluropon Continuum’s advanced performance is backed by a 25-year warranty for extrusion applications and a 35-year warranty for coil applications.

According to Beaudry, “Our warranties are based on actual data. When we look at panels that have 20 or 30 years of exposure, that’s what we build the warranty around. We can see there is no difference between the sample held inside and the one outside for 22 years.”

With the Continuum formulation, the performance was “exceeding our existing warranties. That’s where we got the confidence to increase the warranty.” MM