You've seen the video, right? An image of what looks like an azure-colored metal floor plate appears, backed by some "Streets Have No Name" guitar knock-off. A mysterious hand is getting ready to soak this thing with a squeeze bottle full of water, but the first squirt yields puzzling results. Water beads up and shoots off the surface, leaving the plate bone-dry. Then the title: "What is Ultra-Ever Dry?"
That sequence has played out nearly two million times through YouTube (it's literally more popular than some official Justin Bieber offerings). The video is an endless cycle of items shrugging off water, mud, oil, dirt, paint, and other stickiness with eye-popping ease. Ultra-Ever Dry claims to be a "revolutionary super hydrophobic coating that repels water and refined oils using nanotechnology." Clearly, either the company has made a pact with the devil and gained supernatural powers, or it's got some awesomely talented materials people.
We were just as amazed as most of you were, and we knew we had to try this stuff out. Two hundred dollars and one expense report later, I had a box full of Ultra-Ever Dry cans sitting on the floor of my office, ready to be applied to things various and sundry.
We didn't just want to get some Ultra-Ever Dry and tell you about it, though—we'd much rather showyou. Our call for comments on what we should test it with yielded some excellent ideas. Armed with your feedback, a DSLR, and a cameraman (the ever-patient Steven Michael, who has helped me photograph several NASA pieces), we hit the hardware store for supplies and spent the weekend shooting video.
First: Reader discretion is advised
The Ultra-Ever Dry coatings in their liquid state are based on xylene (bottom coat) and acetone (top coat) and emit powerful amounts of fumes. Applying the coatings to anything inside a house or apartment is absolutely out of the question. Even outdoors, coming anywhere near the stuff requires nitrile gloves and a P100-rated respirator fitted with organic vapor filters.
Bottom line: if you're planning on getting some Ultra-Ever Dry for yourself and applying it, please take the appropriate safety precautions. Many people had previously indicated that they'd love to spray this stuff all over their bathrooms. I sure as hell wouldn't do that in my house.
Water on concrete
Requests that we test Ultra-Ever Dry's ability to repel snow on concrete were common, but that's impossible in my location. I'm in southeast Houston, and snow is something we see once or twice a decade (in March when we did the testing, daily highs were peeking back up into the 80s).
However, you can see above what happens to a small patch of concrete driveway when water is applied to it: the water sluices off the treated section. Examination of the treated area over several minutes actually showed a wet patch creeping further and further down across the treated area, which is almost certainly due to my hand sprayer application of the coating. When properly and evenly applied, the stuff will happily seal your driveway or sidewalk away from water.
At the end of the video, filmed several hours later, something unexpected happens: large drops of water are shown sitting stationary on the treated section. The water doesn't have enough mass to roll down the driveway, so it remains in place until it evaporates. This could potentially mean that a treated driveway after a rain storm might end up wetter than an untreated driveway, depending on how much rain has fallen and how steep the driveway is.
The other possible side effect of coating your driveway is contaminated run-off. The coating job I did resulted in no small amount of excess Ultra-Ever Dry being carried off by water or rubbed off by my fingers the first time each treated object was handled (you can see a thin film of Ultra-Ever Dry back in the first video in the water collecting at the bottom of the toilet, for example). Some amount of Ultra-Ever Dry will almost certainly be carried off of your treated driveway and into your yard and your storm sewer, and I don't know what the potential consequences of that might be.
One week later
A week after filming this, I re-tested the treated section of the driveway and found that exhibited absolutely no superhydrophobic properties at all—it had reverted back to regular driveway. The Ultra-Ever Dry site does make mention that the product is somewhat susceptible to UV exposure, but my application method is more likely to blame than anything else. If you plan on applying Ultra-Ever Dry to your sidewalk or walkway, you must be meticulous with the application. Hand sprayers are simply not going to cut it.
I'm not sure that I'd want to plug the treated keyboard into any computer I care about. Though the Ultra-Ever Dry coating clearly works on the outside, to properly coat a keyboard with the stuff you'd need to disassemble the entire thing—remove keycaps, take out the rubber dome mat and PCB—and hit everything. Even then, the keyboard would likely only be water-resistant, depending on the thoroughness of your coating.
In the video, the water shoots right off the keys and into the channels between them, collecting inside the keyboard body. I didn't bother verifying functionality of the keyboard after soaking it, since a water-repellant surface with water-vulnerable guts doesn't really buy you very much.
Ice cube tray
The ice cube trays demonstrated no substantive difference in their ability to hold and release ice—in fact, ice in the untreated tray slipped out a bit easier than the treated one. This might be due to the trays being brand new and made of fancy blue plastic. Some comments called for testing with metal trays instead, but frankly, I've never seen metal ice cube trays.
(For what it's worth, I had to hunt at Wal-Mart for ice cube trays at all—I've never owned any and never knew anyone without an ice cube maker in their freezer. The blue ones featured here were the only ones I could find.)
Another popular request was to coat a sponge to see how the Ultra-Ever Dry coating bridges the gap between the porous sponge's holes. The observed answer is "sort of well but not that great when you really get down to it."
The Ultra-Ever Dry does make it so that the sponge at first appears to repel water just as much as the treated plate glass, and large globs skitter quickly off of its surface. However, drops of water held in position on the sponge will slowly seep into it. Further, when submerged, the sponge acts like a sponge, amiably sucking up water just as the untreated sponge does.
There don't appear to be any advantages to treating a sponge. I definitely wouldn't wash my car with the treated sponge, as the Ultra-Ever Dry imparts a somewhat rougher texture to things.
Rough textures come into play in our finale video, wherein I douse myself with ketchup and fly down a Slip-n-Slide.
Clothing and ketchup
The efficacy of the Ultra-Ever Dry on the T-shirt and hat are mixed, though as I've been saying, I feel strongly that the results have far more to do with an uneven coating than with the product. Several spots on the T-shirt and hat clearly reject any attempt by the ketchup and mustard mixture to cling, whereas others afford it a bit of purchase.
Worth noting also is the feel of the shirt coated in Ultra-Ever Dry. It felt a bit chalky against my skin—I wouldn't want to wear a shirt or pants treated with the stuff, at least not without an untreated layer under me. It made the fabric feel stiff, and it was not at all comfortable. This is fine for shoes or boots, but not for anything you'd wear on your body. The exception might be a coat or a jacket, but I wouldn't spray Ultra-Ever Dry on anything expensive—the change in texture and the translucent film would detract hugely from a nice coat's look and feel. That said, it definitely worked—mostly, anyway. I would need a more even and far more thorough coating to withstand a soaking like the one my wife made me endure. She would not stop spraying me.
Slipping and sliding—or not
A Slip-n-Slide lets you slip and slide because water acts as a lubricating layer between your body and the smooth plastic. The texture Ultra-Ever Dry brings with it—at least when applied with the hand sprayers—totally undermines that smoothness.
A Slip-n-Slide's plastic surface already repels water pretty well; adding Ultra-Ever Dry makes the surface even more hydrophobic, but also rougher. The result is... well, the result is more of a Slip-n-grind-to-a-halt. Also, I hurt my back because I'm old. I hope you're all happy.
What is Ultra-Ever Dry?
So how does Ultra-Ever Dry work, and what makes it better than mere Ever Dry? It's pretty much impossible to tell based on the information that can be found on the site where it's sold. The information on the two solutions used to create a coating indicates only that the majority of the material in them is a standard organic solvent that will evaporate away. The documents say the solvent contains a small amount of "proprietary ingredient" (and it smells minty), but the information gives you no indication of what that ingredient is likely to be—disappointing, but completely expected.
That's not good enough for us, so we did some further digging. Fortunately, the people behind Ultra-Ever Dry seem to have received some inquiries from individuals who were interested in applying it to equipment that's used in a location where food is handled. So they turned to the FDA to check into whether it was safe to do so. This required the disclosure of information to the FDA, all of which is nicely contained in the document.
This at least contained some information about how it sticks to the surface, which involves a three-part polyurethane adhesive supplied by Bayer MaterialScience. (You can get details on each of the parts, if you care. There is no obvious indication of which of them might provide the minty smell.) These materials were being used to attach another material to any surface you spread them on: an "amorphous, fumed, crystalline silica solid."
These start life as nanoparticles of silicon dioxide. Although nanotechnology is all the rage, the process by which they are "fumed" involves eliminating their nano-ness. In brief, the particles are heated quickly, at which point their surfaces start to fuse. Rather than merging into a single, larger particle, however, only the surfaces stick together. As more nanoparticles stick on, this creates a growing chain of particles with randomly spaced branches. By the time the process is finished, typical particle size is in the micrometer range.
It's easy to see how a branched structure like this could help keep water away from a treated surface, simply by adding a bit of space between a wettable solution and any surface. There's just one small problem here: on its own, the silicon dioxide used to make these particles isn't hydrophobic—it likes to interact with water. This should allow surface tension to bring water through the coating and into contact with the surface being protected. Something else must be going on here.
To find out what, we coated a few samples with Ultra-Ever Dry and shipped them off to Dr. David Hovis of the Swagelok Center For Surface Analysis of Materials at Case Western Reserve University, who arranged to use the facilities to do what the center's name implies they're good at: analyzing the materials. First up, they took a look with X-ray photoelectron spectroscopy, which tells us what elements are present in the coating. This confirmed that the bottom coating was almost all polymer, presumably because it's used to bond a material to the surface.
The top coat, in contrast, contained the promised silicon dioxide. But it also contained a hint of how that material was made to repel water: a fluorinated hydrocarbon was also present. The surface of silicon dioxide materials can be reacted with hydrocarbons to convert it to a hydrophobic surface (this is why you see a variety of materials labeled hydrophobic silica). Fluorocarbons are noted for being hydrophobic, most famously in the form of Teflon.
So what we appear to have is a branched chain of silicon dioxide particles bonded to the surface that's being protected. This creates a three-dimensional mesh that water has a hard time penetrating, because the surface of these particles has been reacted with a fluorocarbon, creating a hydrophobic surface. To confirm this, the Swagelok Center put our samples under an electron microscope, which nicely shows how densely packed the resulting mesh is. Since water can't adhere to any of it and the gaps between chains are so small, the surface tension of water droplets will keep them from ever penetrating the mesh. As long as the coating remains intact, it will remain, as promised, ever dry.
What we didn't test
I did not apply Ultra-Ever Dry to my car, because I'm not insane. I also didn't apply it to anything that I would regularly be touching or interacting with.
Similarly, I was unable to test the Ultra-Ever Dry on any functional electronics. The sacrificial iPhone 3GS I had set aside for the testing unfortunately wouldn't turn on when I pulled it out of the closet—it had apparently overheard what I was planning to do to it and had suicided before I could spray it with anything. Ordering a new phone or expensing more materials was out of the question at that point because I'd already spent $100 on the toilet. Regardless, the Ultra-Ever Dry would make the screen unreadable.
I did some limited testing on cardboard with expected results: the cardboard stayed dry. The strength of the cardboard appeared unaffected by the coating.
Spray paint was a big request, and I had high hopes for Ultra-Ever Dry's ability to repel it. I treated a section of my back fence and we set up the camera and rolled as I busily applied spray paint... and the spray paint stuck just fine. Repeated application with different brands of spray paint yielded similar results, and the paint dried normally. Sadly, Ultra-Ever Dry did not transform my fence into a graffiti-repellent superfence.
Computer components were requested, but I didn't have the opportunity to try to treat a DIY build in Ultra-Ever Dry—by the time I'd done most of the testing, I was running low on daylight, expense account funds, and coating.
I was also unable to get a Raspberry Pi to test with. I couldn't get Jon Brodkin to give me his, no matter how many times I promised that I wasn't going to bury it at the bottom of a toilet bowl filled with potting soil. Honestly, it's probably better that he didn't believe me because that's exactly what I was going to do.
What we learned
Ultra-Ever Dry is amazing stuff, but its applicability isn't universal. You need respiratory, skin, and eye protection to apply it, along with a well-ventilated area in which to do the application (doing it anywhere inside your house or apartment is, frankly, ludicrous). You don't want to put it on anything that's going to come in contact with your body. You don't want to put it on anything you're going to cook with, eat with, or anything you have to see through. You also shouldn't put it on plants, pets, or your children, no matter how awesome you might think the results would be.
On the other hand, it is a great fit for things you need to remain water-, dirt-, and oil-resistant. You wouldn't want to apply it to your car, but you might want to spray it all over your bike. It's not a good idea to coat your underpants with it, but a pair of work boots or work gloves would be just fine. (For the folks who suggested that we apply it to a diaper and then apply the diaper to an actual baby: what is wrong with you?) Driveways, walkways, and other areas with a tendency to collect ice are good candidates, too, but mind the runoff.
Ultra-Ever Dry's efficacy depends greatly on how it's applied. The hand sprayers sold on the Ultra-Ever Dry store work fine for small or limited application, but they produce an uncontrolled, uneven coating. If you're going to use this stuff for real, you need an air compressor and some fine nozzles.
Cost is also a factor. Our two quarts of Ultra-Ever Dry (one quart each of top and bottom coat) and two hand-spray applicators cost $200, including shipping. This proved enough to coat a handful of household items, a toilet, some driveway, a bit of fence, and a Slip-n-Slide. A gallon of top and bottom coat runs beyond $500. It works, but it's pricey.
So it's fun, but is it worth it?
My opinion is that Ultra-Ever Dry is of limited personal usefulness. Aside from maybe your driveway, there aren't a lot of things in the average person's house where the coating would be both cost effective and safe. Its industrial and commercial applications are obviously a lot broader—and it's priced to reflect that.
From a perspective of science, the material is a clever mesh of silicates with a dash of fluorine secret sauce. The majority of the stuff is solvent and evaporates when you apply it—in a very stinky fashion—and what's left behind is a translucent chalky coating. You don't want to get it on your skin or in your mouth and eyes.
Still, I'd be lying if I said I didn't have a hell of a good time spraying it on stuff and watching the water and dirt roll off.Some extra bloopers and silliness—for those of you who want one last little peek.
We sincerely hope you've enjoyed watching our first major video feature. We're definitely seeking feedback on how to improve, both technically and stylistically, and we'll be watching the comments.