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ramé-hart instrument co. June 2014 Newsletter |
| Ten Ways Superhydrophobicity Will Improve Your Life |
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Here at ramé-hart, we've been measuring contact angles for over fifty years. Back in the early days about the only surface that we ever measured with a water contact angle over 150° was the lotus leaf.1 In fact, the term "superhydrophobicity" did not even exist until 1991. In the past twenty years several hundred US patents have been granted for producing superhydrophobic surfaces or products that employ them. Strident progress in nanotechnology has contributed to the development and optimization of nanoscopic topography which leverages the benefits of the plastron effect.2 Recently we've seen a rapidly increasing number of commercial applications for superhydrophobicity. Our objective this month is to detail 10 of them and explain how they will make your life better. 1. Some people like to wash their car. Other people (like my neighbor Gene) like to go to the car wash and pay other people to wash their car. I have to admit that personally I don't fall into either group. While I do like a clean sharp-looking car, I can think of a hundred other things I'd rather be doing on Saturday morning - which is why I was excited to hear about Nissan's self-cleaning car.3
The key is a paint called Ultra-Ever DryŽ which is both superhydrophobic and oleophobic (oil-repelling). It was developed by engineers at the Nissan Technical Centre in the UK and is currently being tested on the Nissan Note in Europe. While it's too soon to say if this technology will become standard equipment, if the long-term durability is good and the cost is reasonable, you can count on a lot of interest from people like myself who like clean cars but don't like cleaning. 2. There are few household tasks that rank lower than unclogging the toilet. Enter Rubbermaid Clean & Dry Plunger treated with NeverWet superhydrophobic coating - water just beads up and rolls off helping you keep your floor free of unsanitary drips after use. In theory, this is a great product.
Based on the reviews, however, this product is not quite ready for primetime. Users report that the superhydrophobic coating wears off after a dozen or fewer uses. Others claim that by simply touching the surface or washing it off with soap will deactivate the water-repelling properties. This may explain why reviewers on Amazon and Rubbermaid's own website give it a mere two out of five stars.4 3. If you would like to treat your own things with NeverWet, it's available commercially from Rustoleum on Amazon and at Home Depot. In my case, I treated my Puma Clyde suede leather sneakers and the coating does in fact work...for awhile.5 However, it leaves an annoying haze on many surfaces and does require a two-step application. Competitors like Hydrobead are promising a better solution with only a one-step application. 4. Smartphone and tablet makers are working feverishly to develop coatings and methods that make their products both superhydrophobic and superoleophobic.6 59% of smartphone users admit to having reached into a toilet to retrieve a phone.7
This problem coupled with rain and drink spills make a water-repellent shell a compelling proposition - so much so that people are willing to pay $60 or more for aftermarket treatments like Liquipel. These products promise varying degrees of water repellency. Touchscreens are made to be oleophobic to resist finger grease. 5. Paint. This is a big market. Just walk through a Lowe's or Home Depot paint aisle. Now imagine that in twenty years, half of the paint sold in the US will be hydrophobic. It could happen. In 1999 Sto AG began selling a superhydrophobic paint called Lotusan in Europe. Five years later they began selling it in the US. However, it has not really become the hot seller that we all expected it to become. It's only available through a very narrow distribution channel and you have to buy 5 gallons at a time. We've been trying to get our hands on a sample of it for some time but have had no luck. Bottom line: the market for superhydrophobic paint is pretty ripe if someone can figure out a better way to do it and distribute it. 6. Consume all your condiments and throw out less. That's the premise behind LiquiGlide.8 Once this technology hits the market, it could revolutionize the way we package food, petroleum and oils, and any other viscous liquid. LiquiGlide claims to be the first and only permanent and durable wet slippery surface technology.
Technically, LiquiGlide is not a superhydrophobic surface; rather, it's a permanently wet surface which allows thick liquids like ketchup and laundry detergent to slide freely. Nonetheless, it will make your life easier. Full disclosure: LiquiGlide was developed at MIT with the help of a ramé-hart Model 590. 7. Glass. Imagine never having to wash windows again - or owning a car that needs no windshield wipers.9 That's the mission behind the work of a number of research teams. Durability seems to be the key obstacle to overcome: glass surfaces can be made superhydrophobic using a variety of competing methods but keeping the surface that way for long can be a challenge. Once that problem is solved, you may be able to remove cleaning windows from your list of least favorites chores. 8. I bought a superhydrophobic shower curtain once.10 It was really nice new but the self-cleaning properties soon dissipated with use. Soon it was just like any other shower curtain: filmy and a magnet for mold. Researchers are working on methods for fabricating more mechanically durable superhydrophobic surfaces.11 Self-healing hydrophobic layers as well as hierarchical structures with large scale features which protect the smaller nanoscale surfaces are being explored as possible solutions. 9. Anything outdoors that gets wet. If you're a camper or outdoors person, you know that dry equals happy and wet equals unhappy. Happiness is the promise behind Kiwi's Camp Dry Heavy Duty Water Repellent which uses a silicone formula to make boots, gloves, tents, and any other type of outdoor gear water repellent. It may not classify as superhydrophobic but perhaps the next generation of this product will be. The idea that you can spray on a coating and turn just about any surface into a water repellent hydrophobic surface is quite compelling. We haven't tested this product but the Amazon reviews indicate that it works well for most people who have tried it.12
10. My new ride is a Kawasaki Ninja 1000 (shown below). And let's face it: there's nothing on a motorcycle that should ever be wet. I could really go for a superhydrophobic seat. After making an unscheduled diner stop to avoid a quick thundershower, it would be nice to return to a dry seat. I could also go for a non-wetting windscreen and face guard. After all, motorcycles don't have wipers - so it would be nice to get the water off to improve visibility when you are caught in the rain. Lastly, I could go body parts, tank, cowling, and engine covers all coated with a non-wetting treatment like Ultra-Ever DryŽ (see 1 above) just to keep the bike looking nice and to be able to put on a few more miles between washings. There are some products (like Raincoat) which address the visor and windscreen surfaces. However, a lot of work has yet to be done to address all of the items on my superhydrophobic motorcycle wish list. 1 See
http://en.wikipedia.org/wiki/Lotus_effect |
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Imaging Upgrade Kits |
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We recognize that the acquisition of a new
instrument is a capital acquisition that is anticipated to bear fruit
for many years to come. We've been making goniometers since the 1960s
and, believe it or not, some of the original instruments are still in use
today (Model 100-00 with microscope). In the 1990s we transitioned from
microscope-based tools to camera-based software-driven products which
have proven to be much more user-friendly, more powerful, and most
importantly, more precise. However, technology is ever changing. For
this reason we have, for many years, offered a number of imaging upgrade
kits in order to help you preserve your instrument investment. The
current kits include the following: 1. p/n 100-12-U1-UPGF will upgrade any F series instrument (e.g., F1, F3, or F4) to our current newly released U1 Series camera which operates at 100 fps.1 The upgrade kit includes an upgrade to the current version of the same edition of DROPimage that you currently license. 2. p/n 100-12-U-UPG will upgrade any 00 Series analog system (with legacy frame grabber card) to our new U1 Series camera along with our current DROPimage software. 3. p/n 100-12-U1-00-UPG will upgrade any legacy Model 100-00 with microscope to our current U1 Series camera. This kit also includes our DROPimage Standard software. If you have a dated system that is in need of rejuvenation, contact us today for details and a quotation on the best upgrade path for your tool. 1 For more on our new U1 Series camera, see the second article in last month's newsletter here: http://www.ramehart.com/newsletters/2014-05_news.htm |
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Regards,
Carl Clegg |
