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Science Technology

Nanotech Coating Prevents Fogging 201

MilSF1 writes "MIT scientists have applied for a patent on a coating process that reduces or eliminates fogging on glass surfaces (car windshields, eyeglasses, etc). The new coating was described today at the 230th national meeting of the American Chemical Society."
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Nanotech Coating Prevents Fogging

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  • by Ckwop ( 707653 ) * <Simon.Johnson@gmail.com> on Tuesday August 30, 2005 @08:03AM (#13434695) Homepage

    Ever wanted a shave in the shower but your hand-held mirror fogs up? Rather than buying this patented glass you can resort to a low-tech solution: Rub a little shaving foam over the glass and the wash the excess off so you have a thin, clear, greasy film on the glass.You'll find that the mirror no longer steams up.

    The reason this works is because the greasy film causes much larger drops to coalesce on the mirror than you would normally get. These larger drops don't refract the light nearly and as a result are essentially transparent. This simple trick allows me to insure my sideburns are the same length even when under the most horrendous time presure.

    See, who says that Physics can't be useful in everyday situations?


    • I use an electric razor, you insensitive clod.
    • Rub a little shaving foam over the glass
      Yes, I use Vaseline to get a pretty look and start every day like a soap opera.
    • by dsginter ( 104154 ) on Tuesday August 30, 2005 @08:29AM (#13434841)
      If you've got a hand-held mirror, then you can just heat it up under the shower water. The "fog" appears on the mirror because it is lower temperature than the water vapor. When this water vapor comes in contact with the lower temp mirror, it loses the energy that it needs to stay in the form of vapor and turns back into water. This "fogs up" the mirror.

      If you just heat up the mirror, then it will no longer suck the energy out of the water vapor and cause the fog.
      • I can't recall where I heard this, but some Japaneese hotel rooms feed the hot water for the shower through a miniature radiator behind the mirror. This way, running the shower automatically heats the mirror so that it doesn't fog.

      • I believe that Chuck Yeager used to use shampoo on the inside of his canopy to prevent it from fogging over. IIRC the Air Force had a similar substance, but it was very expensive and they ran out one day.
    • It tends to last about a week as well which is nice. I've been doing that trick for ages.

      But side burns man? Do you have an afro too? If not you need one, you should go for the insane druggy look.
    • Why use expensive shaving foam?

      spit on it and rub it around. fog prevention the low tech way.

      Most divers know of this trick, spitting in your goggles and then rubbing it around gives you fog free facemask for the duration of your dive.
    • This does not help you in such cases as:
      Your car
      Your face gear (glasses, goggles, masks)
      Home windows (sometimes they get foggy)

      Also, it would be nice if I didn't have to waste my expensive shaving cream on my mirror (not that I use shaving cream, which is another problem).

      They do have those mirrors that connect to your shower head and it trickles down warm water. The warm water keeps the mirror at the same temp as the shower, and you get no fog.
    • That's kinda neat but the moisture causes other problems in the washroom besides mirror fog. Like mildew, mold, etc. So the best idea (like with good code) is to make sure the problem never occurs. ie use an exhaust fan.
  • by jkrise ( 535370 ) on Tuesday August 30, 2005 @08:04AM (#13434705) Journal
    XP + Nanotech coating = Transparent Windows! Probly explains the long delay in releasing LongHorn...
  • And want a cheaper solution for keeping your bathroom mirror fog free, before you get in the shower/bath/whatever, rub some shaving foam into the glass. not alot - about a cm^2 blob. then rub with a very damp cloth so it dissapears and u can see your reflection.

    Have the shower!

    Get out, go to shave, and voila! No foggy window!

    This nanotech gaff will definately work wonders in the car. Hey, it will mean I wont have to bust my gut when I get in having to clean every window of fog while my gf drives
  • Sorry (Score:3, Funny)

    by FinestLittleSpace ( 719663 ) * on Tuesday August 30, 2005 @08:07AM (#13434734)
    I won't believe any of this until there is a Podcast released on it.
  • Fog-X (Score:5, Informative)

    by coke_scp ( 892822 ) on Tuesday August 30, 2005 @08:10AM (#13434748)
    The people who make rain-x, which works rather well itself to deflect rain, also make fog-x, which I've tested on a steamy bathroom mirror, and it works perfectly.
    • But it leaves a tiny layer of water on the surface - the condensation is just the same, only instead of billions tiny droplets, it forms one flat layer. This thing claims to keep your mirror dry.
      • Re:Fog-X (Score:2, Informative)

        by pecko666 ( 684783 )
        No. This solution also creates thin water film on the surface.
        As a result, the droplets flatten and merge into a uniform, transparent sheet rather than forming countless individual light-scattering spheres.
      • Re:Fog-X (Score:2, Insightful)

        by Ihlosi ( 895663 )
        It doesn't, because doing so would violate certain thermodynamic principles in horribly gruesome ways.

        If there is an object with a temperature below the dew point, water will condense on it, regardless of what the surface is like.
    • I've never seen Fog-X, though maybe you're just making up a stupid but believable name for Rain-X Anti-Fog [rainx.com]... That antifog stuff would be great if it lasted through more than a few showers (on a bathroom mirror), or more than a week of driving in the fall (on the inside glass of a car without an effective defogger).
  • by bigtallmofo ( 695287 ) on Tuesday August 30, 2005 @08:14AM (#13434767)
    MIT scientists have applied for a patent on a coating process that reduces or eliminates fogging on glass surfaces. The new coating consists of a highly acidic chemical that melts the glass into a thick green goo. While the glass (now known as green goo) possesses none of its original qualities including transparency, it has also been shown to provide a 5% or greater resistance to fog.

  • by se2schul ( 667721 ) on Tuesday August 30, 2005 @08:16AM (#13434781)
    ...they simply spit in their masks to prevent fogging.
    • Yeah, and you know what? That doesn't work. At all. As far as I can tell it's just something that divers tell newbies to make them spit on themselves. I tested that stuff from the Rain-X guys on my car windshield, too, but it left a film of crap on my windshield that was almost as bad as the fog was. It might work better on a diver's mask, I dunno, I haven't been diving in years. It might also have improved in the last few years -- I stopped using it almost immediately.

      So if MIT can get rid of my foggy gl

      • Oh, it certainly works if you do it right. 1) Make sure that you cover the entire glass surface inside and out with spit. 2) Rinse lightly. If you rinse out the entire saliva film, you will fog. It's the film that prevents the fogging. 3) Dive immediately. Leaving it more than a minute or 2 will cause fogging for some reason. BTW, I have 12 years of diving and over 800 dives without a fogged mask :)
      • Rain-X works by making the surface more greasy (water-repellent) which causes the drops growing big quicker. It is supposed to make a chemical bond with glass but the problem is that the bond is very unstable. And the greasines causes other yuck and dust to stick more easily to the windshield.

        The described invention works by opposite effect - like a detergent, breaking dropplets to form a uniform water film. The polymer they use for attaching silica microparticles can be effective on its own and it is proba
    • I do this in my car on cold winter nights, but all my dates find it repulsive.

  • Fogging of glasses is a problem. The visor problem's been largely solved what with Foggy Masks, Fog City films but it's still a problem for those who wear glasses.

    • I like to ride motorcycles while wearing glasses, a monocle, an eyepatch, and a visor. And a blindfold, just to make it complete.
    • Fog City Shields, for those who don't know, is just a plastic sticker that stands a bit off the face sheild. The air insulating layer helps prevent fogging, just like a two-layer ski goggle.

      There are a few problems with it:

      1) Even a brand new Fog City film makes the shield noticeably less clear
      2) the dual-layer sheild has bad prismatic effects especially at night.
      3) the plastic is extremely soft and easily scratched even by cleaning
      4) resistance to fogging seems to decrease over time. (Perhaps they

  • awsome (Score:4, Insightful)

    by Adult film producer ( 866485 ) <van@i2pmail.org> on Tuesday August 30, 2005 @08:18AM (#13434786)
    One of the worst things about wearing glasses up north is the fogging.. being outside in -25c temperatures for even a few minutes and glasses get cold enough that they fog up when paying for gas, or shovelling snow, etc.. pain in the ass. I welcome this new technology :)
    • fogging in winter is not a problem in the great white north.

      when I lived in upper michigan, go out to shovel and then return inside, your glasses FROZE UP.

      no amount of nanotech or other fancy coatings can stop that from happening.

      it's not fog, it's ice. this is most obvious if your homes heating system is properly designed and adds humidity to the air. a 0degF pair of glasses getting in contact with warm humid air = nice thin layer of ice.

      If you want to solve the fogging issue, get a decent quality eyeglas
      • If you want to solve the fogging issue, get a decent quality eyeglass cleaner. mine has had an anti-fog agent in it for over 3 years now and it's the cheap crap they give you at D.O.C. eyeglass centers.

        DOC? Department Of Corrections? Are you posting from prison?
  • Great news for scuba (Score:5, Informative)

    by vstanescu ( 522393 ) on Tuesday August 30, 2005 @08:18AM (#13434787) Homepage
    May be this will finally replace the old method of spit and rinse, because all those special glasses on the scuba masks had no effect until now. For those who don't know, if you want your scuba mask to be perfectly clean of fog, you have to spit inside it when it is dry, then rinse very fast with sea water (just to make the glass clear enough but probably without rinsing all the substances in the saliva from the glass) then put it on the face and dive immediately. For those who forgot doing this, even the best tempered glass became foggy in a few minutes in cold water.
    • by oneandoneis2 ( 777721 ) * on Tuesday August 30, 2005 @09:26AM (#13435190) Homepage
      Oh, come on, it's nowhere near *that* fussy!

      You spit in it whether it's dry or not. Then you rub it into the glass with a finger, and give it as much of a dunking as you like in whatever water is around. Then it'll stay fog-free unless you allow it to dry out - so either put it on & trap the moisture in, or leave your mask laying flat with some water inside.

      Of course even the best tempered glass will fog: tempering isn't supposed to provide anti-fog properties, it's used as a safety measure.

      Lastly, it's not like you can't buy bottles of anti-fog from any half-decent dive shop that'll do at least as good a job.

      (As a UK diver, I might add that one downside of spitting in your mask is that on very cold winter dives, your spit will freeze solid on the glass before you can do anything useful with it ;o)

      • Lastly, it's not like you can't buy bottles of anti-fog from any half-decent dive shop that'll do at least as good a job.

        I've been less than impressed with the anti-fog. I've tried a couple types, and I just find my spit works better. It's also a lot more convienient. :)
        • I've been less than impressed with the anti-fog. I've tried a couple types, and I just find my spit works better. It's also a lot more convienient. :)

          It's also cheaper & impossible to forget or run out of :o)

          But the anti-fog from my local shop is actually better than spit - my spare mask always, but always, fogs up. It's had every cleaning treatment known to man, but no amount of spit stops it fogging.

          A few drops of anti-fog, however, and it behaves itself perfectly. Annoying, but true!

    • You can also use gel toothpaste. Get the cheapest you can find and use your finger to spread some on the glass. Wait for it to dry then rinse it out. It works just as well as anti-fog and cheaper too!
  • 1947 solution (Score:5, Interesting)

    by Spy Handler ( 822350 ) on Tuesday August 30, 2005 @08:20AM (#13434790) Homepage Journal
    The X-1 had a bad problem with its windshield fogging up and frosting. On the flight before it went supersonic, according to "Yeager: Autobiography":

    "My crew chief applied a coating of Drene Shampoo to the windshield. For some unknown reason it worked as an effective antifrost device, and we continued using it even after the government purchased a special chemical that cost eighteen bucks a bottle."

    • Re:1947 solution (Score:4, Informative)

      by Anonymous Coward on Tuesday August 30, 2005 @12:42PM (#13437160)
      Chuck Yeager has a lot of anecdotes about his crew chief. The guy was a genius when it came to common sense, solving problems, and getting things done. A true hero behind the scenes, the best there was.

      If scientists and normal people would read this stuff, I am sure they would rediscover all sorts of solutions to common problems.

  • by AltGrendel ( 175092 ) <ag-slashdotNO@SPAMexit0.us> on Tuesday August 30, 2005 @08:22AM (#13434797) Homepage
    Basically, they take a glass/plastic mix of microscopic particles, coat the glass and then subject it to high heat, making a glass sponge (Very simplified explination).
    I always think of nanotech as something more novel. If this were thousands of billions of tiny squeegee bulldozers one micron across moving the water to the edge of the glass, then I'd consider it nanotech.
    • Applying a patent for a sponge just doesn't sound good enough. And hey, maybe later they can extend the explanation of the patent to include the standard sponges used to wash your windows.
      You pay MIT every time you buy a sponge!
    • by qval ( 844544 ) on Tuesday August 30, 2005 @08:44AM (#13434926)
      It's being called nanotech because it uses nanoparticles, very small groupings of atoms, containing 100s or 1000s of atoms. Government money for nanotech research applies if you're working with objects smaller than 100nm in some dimension. IIRC, carbon nanotubes are sized roughly 5nm and larger in diameter.

      The current state of the art of nanotech is not nanobots that can cure cancer. That's just what people speculate might come out of this technology, but how often is such exhuberance warranted? where's my flying car?

      Also, by the way, something one micron across would be microtech by definition, not nanotech, but that's more me being a stickler than informative...
      • It's being called nanotech because it uses nanoparticles, very small groupings of atoms, containing 100s or 1000s of atoms.

        This is a really lame definition, because that means we've had nanotech unknowingly for thousands of years. Although previously, 'nanotech' materials were found accidently and were created with bulk processes that operate on ordinary scales, and there was no physical explanation for why the materials worked. Now that we understand the properties of things like silica beads, and have w
      • something one micron across would be microtech by definition

        Not if the components used to construct it were nanoscale.

        This would, in my opinion, be a better use of the term nanotech - technology consisting of nanoscale components. Nanoscale coatings for various things have probably been available for some time.
      • We just called this "chemistry."
    • by k98sven ( 324383 ) on Tuesday August 30, 2005 @09:04AM (#13435034) Journal
      So why is anything being called nanotech?

      Nanotech is a buzzword. It doesn't really mean anything. It's never meant anything. It's just a new word used by chemists, solid state physicists, and others to get funding and excitement around the same stuff they've been doing for quite some time.

      • Not an official definition here, but it's nanometer scale engineering. Saying that the above application is "nanotech" is something like calling a parking lot "architecture".
        • Not an official definition here, but it's nanometer scale engineering.

          So is all chemistry. But not all chemistry gets to be called "nanotech". I personally do 'engineering at the nanometer scale', yet within an area which is not graced by the 'nanotech' buzzword (enzymatic catalysis). But I have no sour grapes about that.

          Because as I said: the term is complete nonsense. If you apply your skills to one area it's 'nanotech' when applying the exact same skills to a different area isn't. A good portion of the p
  • Motor helmet screens come with this kind of anti-fog layer for several years already, see for example: http://www.bellmotorsports.com/helacc.shtml [bellmotorsports.com] or http://ecom1.sno-ski.net/goggles.html [sno-ski.net] for fog free goggles. So did MIT do their background research before starting this patents application?
    • So did MIT do their background research before starting this patents application?

      Those products appear to be using (a) an attachable "sticker" or (b) a spray. Neither of which I would call particularly permanent. Anti-fog coatings (in general) have been around for years. The concept of applying them at manufacturing time using the particular process detailed in TFA is presumably the novel basis on which they are applying for a patent. If not, one would hope the Patents office will deny them the patent.

  • by BadDoggie ( 145310 ) on Tuesday August 30, 2005 @08:34AM (#13434867) Homepage Journal
    Funding for this study was provided by the Defense Advanced Research Projects Agency (DARPA) and the National Science Foundation (via the Materials Research Science and Engineering Centers, or MSREC)

    I'm not a raging anti-patent looney screaming about the need for a free utopioan society, but if funding for this was provided by the public, surely the results belong to the public and the methods belong in the public domain rather than to MIT for the next 17-34 years.


  • Ski Goggles (Score:2, Insightful)

    by complex17 ( 783342 )
    Just the other week I was nearly driven crazy by a layer of fog that had snuck in-between the two lenses of my ski goggles. It took several days of sitting them next to a heater before the problem was fixed. Presumably this couldn't happen with totally fog-free lenses.
    • Fogging ski goggles is a real safety issue. Your breath always manages to get up into them, especially if you are wearing a face mask.

      When I was climbing Mt Rainier I had to wear goggles on the last half due to strong winds and I was practically blind from the iced up fog. No attempts to rewarm them in my jacket worked, it was a real pain. Same thing happens on winter climbs in the Presidentials in NH. I've even tried applied coatings like "cat crap" but they don't work.

      A coating that works on plastic t
    • It seems to vary between individual goggles.

      In my experience, the problem is if the seal between the layers is imperfect or compromised, moisture gets between the layers, and you will always have fogging problems. You might as well toss the goggles, you will always have problems with them.

      But if you find a pair of goggles that happens to have a perfect seal, and you never mess with it, they will never fog (at least between the layers).

      I have an old, cheap, scratched up, duct-taped pair of Alpina goggles

  • I look forward for swimming glasses which do
    not fog up. They usually do, evenso the packages
    claim they have a coating which should prevent that. When swimming competitively, we had a low-tech solution: spit on the inside of the goggles would prevent fogging up.
  • I don't know why they're bandying the term "nanotechnology" around, because it's not. It's a silica coating that prevents fogging. In fact, the only reason this made it to slashdot is because the term "nanotechnology" was used in the title of the original press release [eurekalert.org]. You'd think the people at MIT and the ACS would know better.

    the science and technology of building electronic circuits and devices from single atoms and molecules.

    This does not meet those criteria.

    • I bet that MIT does know better (they know where the funding is). As for your definition of nanotechnology, he science and technology of building electronic circuits and devices from single atoms and molecules, this seems incorrect. After all, a very large diamond is still a single molecule, as is IIRC anything made of metal. Nanotechnology is about working with small things.
    • nanotechnology | noun the branch of technology that deals with dimensions and tolerances of less than 100 nanometers, esp. the manipulation of individual atoms and molecules.

      (from the dictionary on my desk )

      However dictionaries do disagree on this ..and some give this

      nanotechnology [Show phonetics]
      noun [U]
      an area of science which deals with developing and producing extremely small tools and machines by controlling the arrangement of individual atoms

      dictionary.cambridge.org [slashdot.org]

      Though i supp

  • From the article: "The new coating prevents this process from occurring, primarily through its super-hydrophilic, or water-loving, nature [...]"

    I recall this being one of the properties of nano-coated self-cleaning glass such as Pilkington Activ or PPG SunClean, so does that not already provide the same anti-fog advantages?
  • by Lord Byron II ( 671689 ) on Tuesday August 30, 2005 @09:38AM (#13435274)
    As any scuba diver will tell you, spit works wonderfully to prevent your dive goggles from fogging up.

    And if you wish for a slightly higher tech solution, your local auto parts store sells a product called Fog-X which when applied to glass, prevents fogging.

  • ... have applied for a patent...

    Which means I'll be old and gray before I ever wear a pair of glasses with this stuff or own a car that has a windshield with it -- even if it's a potentially cheap solution.
  • by snowwrestler ( 896305 ) on Tuesday August 30, 2005 @10:12AM (#13435546)
    An engineer named Richard Hartman developed antifog glasses for whitewater kayaking based on this concept several years ago. He developed a hydrophillic coating that was baked onto the lenses, and which prevented the formation of fog droplets. He even offered them for sale for a time--send him your prescription and he would send back a pair of glasses. I don't think he does that anymore.

    Here [boatertalk.com] is a recent post describing his work.

    Here [boatertalk.com] is a post from 2001 answering some questions about the glasses.

    Here [boatertalk.com] is a search on the Boatertalk forum for most posts about it.
  • by Thai-Pan ( 414112 ) on Tuesday August 30, 2005 @11:10AM (#13436117) Journal
    I have a product called FogX that I've been putting on the inside of my car windshield for years. No fog, no hassle, low cost. I've also been applying it to bathroom mirrors and such. Am I completely missing something, or is this not exactly a breakthrough?
    • According to the article:

      Researchers have been developing anti-fog technology for years, but each approach has its drawbacks. Some stores carry special anti-fog sprays that help reduce fogging on the inside of car windows, but the sprays must be constantly reapplied to remain effective. Glass containing titanium dioxide also shows promise for reduced fogging, but the method only works in the presence of ultraviolet (UV) light, researchers say.

      "Our coatings have the potential to provide the first perman

  • This is great news for slashdotters. Now when you're making out with your girlfriend in the backseat of the car ... oh, wait. Never mind!
  • It amazes me that this kind of thing slips by the slashdo[tt] editors regularly. Bad science masquerading as legitimate theory. But I really don't see how nanoparticles are going to prevent people from getting flogged. On the one hand you've got a bunch of inanimate particles on the nano level and on the other hand you've got a guy in an executioner's hood holding a cat-o-nine tails above you. What possible match is there? The guy in the executioner's hood is going to win every time. Trust me. I know
  • Already installed in my car (a 1994 model), and requiring no re-application or chemicals, no electricity, and once activated it stays activated until manually deactivated. Even in a deactivated state this amazing invention provides an invisible barrier to dangerous atmospheric gas -- such as carbondioxide and powerful solvents such as dihydrogenmonoxide often found in highly toxic acid rain.

    This device is designed with macro technology (buzzword: MacroTech) -- which is not plagued by the extremely dangerou [crnano.org]
  • The real issue (Score:2, Insightful)

    by Bryansix ( 761547 )
    It seems to me that people have all kinds of solutions to keep surfaces from fogging or to make the water that does condense on the surface to remain clear. However there are two things that seem to be difficult to do with any of these solutions.

    They are to make the solution permanent and durable and...

    To make the solution of a material that will not distort your vision when looking through the surface of the material.

    So yes, you could apply rain-X every month or wipe shaving cream on your surface

All laws are simulations of reality. -- John C. Lilly