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Spray on Cheese, Spray on Hair; What Will They Think of Next?
February 3, 2010 9:56 AM   Subscribe

Spray-On Glass! Immaculate clothing and easy house-cleaning for all! A German company, Nanopool (may need to run through google translator), has developed some sort of mad science/flying car future-style fluid suspension of SiO2 that can be applied to apparently any surface with startling applications. I am entertained by the idea that wax fruit may be replaced by glass fruit... as it were. Additional details, but no real specs here.
posted by LD Feral (53 comments total) 6 users marked this as a favorite

 
Article on the topic from PhysOrg. Apparently, there's only one distributable photo for the product.
posted by KGMoney at 10:02 AM on February 3, 2010


Yeah, here's what I don't like about this company. They claim the product is patented, but then they refuse to say exactly how it works.

"When asked about how the technology works, Neil, said 'In essence, we extract molecules of SiO2 (the primary constituent of glass) from quartz sand, and then we add the molecules to water or ethanol. Unfortunately, as they say in the movies , if I told you any more …..'"

One of the primary points of a patent is that you don't have to worry about disclosing how something works, and in fact you have to disclose it to get the patent. That they're still being coy about it suggests that either it's a bit snake-oily, doesn't work as well as claimed, or that they screwed up the patent rights (e.g., didn't file outside of Turkey, where it was originally invented). If they screwed up the patent rights, expect to see Nanopool get demolished when DuPont copies the invention.
posted by jedicus at 10:06 AM on February 3, 2010 [11 favorites]


So, when consumers start coating every surface in their house with this stuff, will the dust content in their homes heavily comprised of silicon particles when the coatings are worn down? What kind of health issues are we looking at here? At the very least, it seems like you would have a lot of sandy nasal discharge.
posted by Burhanistan at 10:06 AM on February 3, 2010


It sounds too good to be true: a non-toxic spray invisible to the human eye that protects almost any surface against dirt and bacteria, whether it is hospital equipment and medical bandages...

This is like how my glass windows are always spotlessly clean and germ-free. Also why I don't ever wash my ceramic dishes.
posted by DU at 10:08 AM on February 3, 2010 [3 favorites]


What kind of health issues are we looking at here?

Probably rampant silicosis. Refinishing a floor that had this stuff sprayed on it would be kind of a nightmare.
posted by jedicus at 10:09 AM on February 3, 2010 [3 favorites]


Nice to see I wasn't the only person who wondered how quick it'd start flaking away into the air. Also, how would one get it off the seeds/fruit? Ah well.
posted by LD Feral at 10:19 AM on February 3, 2010


we extract molecules of SiO2 (the primary constituent of glass) from quartz sand, and then we add the molecules to water or ethanol.

Sand + water = mud
Sand + ethanol = alcoholic mud

Thus ends today's chemistry lesson.
posted by Cool Papa Bell at 10:21 AM on February 3, 2010 [4 favorites]


Sand + water = mud

If you call it a colloidal suspension you can charge more.
posted by Freon at 10:23 AM on February 3, 2010 [23 favorites]


> we extract molecules of SiO2 (the primary constituent of glass) from quartz sand, and then we add the molecules to water or ethanol.

So basically they've developed homeopathic glass?
posted by mosk at 10:32 AM on February 3, 2010 [11 favorites]


Silicon dioxide isn't soluble in water or alcohol at least at room temperature and pressure.
That's why you can use glass bottles to hold quantities of water or alcohol for long periods.

Seconding the mud/homeopathic glass theory.

And as we all know... If you aren't part of the solution, you're part of the precipitate.
posted by Balisong at 10:40 AM on February 3, 2010 [5 favorites]


So basically they've developed homeopathic glass?

Cures lacerations?
posted by RustyBrooks at 10:42 AM on February 3, 2010 [1 favorite]


Sand + water = mud

Actually, sand + dirt = mud. Sand + water = wet sand. Or have you never been to the beach?
posted by The World Famous at 10:47 AM on February 3, 2010


Actually, sand + dirt = mud. Sand + water = wet sand. Or have you never been to the beach?

You're so close.
posted by youthenrage at 10:50 AM on February 3, 2010 [3 favorites]


Mmm, I can't wait until they spray this liquid asbestos all over my fruit. I bet it will make it even more delicious.
posted by IanMorr at 10:55 AM on February 3, 2010


You're so close.

Curses.
posted by The World Famous at 11:01 AM on February 3, 2010


They claim the product is patented, but then they refuse to say exactly how it works.

Well, there's an easy solution to this. A search of patents held by nanopool doesn't give any results, but a search in the German trademark register shows that several derivatives of "nanopool" are registered as trademarks by one Lilly Schwindt. Using the name "Schwindt" in the espacenet patent database of the European Patent Office, one quickly stumbles upon this patent application by Sascha Schwindt and the "Foundation (Stiftung) Nano Innovations". How it is supposed to work should in principle be explained inside (in German, I'm afraid).

You're all welcome.
posted by Skeptic at 11:04 AM on February 3, 2010 [10 favorites]


when consumers start coating every surface in their house with this stuff

... I start selling a toy machine gun that fires stones.
posted by CynicalKnight at 11:11 AM on February 3, 2010 [1 favorite]


This sounds like something I'd get in Kingdom of Loathing.
posted by sciurus at 11:15 AM on February 3, 2010 [9 favorites]


I can hardly wait for the remake of "House of Wax" as "House of Glass".
posted by happyroach at 11:28 AM on February 3, 2010


I can easily see the applications in healthcare. There glass is easier to clean and make anti-septic than plastic, rubber, cloth. I'm not sure I need my sofa to get a coating of this stuff though.

I'd be interested in hearing more about it though.
posted by Ruthless Bunny at 11:30 AM on February 3, 2010


You know I was just thinking earlier today that my chances of dying horribly from mesothelioma are way too low. Glad to see somebody's working on that.

And as a side note, this sounds remarkably like every Shadowrun-playing munchkin's favorite substance, Dikote.
posted by Pope Guilty at 11:32 AM on February 3, 2010


This sounds pretty sketchy. However, assuming for a moment that the company and the process are legit, can anyone give me some input on this question...

It seems to me that the water or ethanol would evaporate away leaving behind silica. It's been a long time since chemistry class so excuse me if I'm missing something but silica doesn't melt into glass until it reaches ~2000 Celsius. I don't understand how this does anything except leave a fine coating of sand on whatever is sprayed. What gives the silica left behind any more cohesion than it had to begin with?
posted by Babblesort at 11:33 AM on February 3, 2010


SiO2 is sand people, not asbestos. If you think that using a ridiculously small amount of this stuff to coat things and having it flake off is dangerous, I'd advice staying away from beaches. Silicosis might be something to worry about if you work in the factory that makes the stuff (and maybe if you were doing a crapload of refinishing without a mask on, as Jedicus suggests), but I'd be surprised if that's going to be a serious health problem.

I am skeptical of whether the stuff works as advertised, but if it does anything at all, I think the novelty is entirely in the application methods, and not the contents.
posted by ErWenn at 11:36 AM on February 3, 2010


Time for a new Bond film:

Glassfinger.

"Glass .... fingahhhhhhhhhhhh"
"Such a crass fingahhhhhhhhhhhhhh"
posted by freecellwizard at 11:38 AM on February 3, 2010


ErWenn: The problem isn't what it's made of, it's that it's so small. The particles of sand we're talking about are 300 times smaller than a red blood cell. We don't actually know what will happen if we breathe this stuff.
posted by JDHarper at 11:50 AM on February 3, 2010 [2 favorites]


SiO2 is sand people

Someone page Charlton Heston, stat!
posted by explosion at 11:59 AM on February 3, 2010 [5 favorites]


Bah, they've done a terrible job explaining their own science.

Typically, when people think of a solution of a substance in water or some other liquid such as ethanol, they think of it dissolving into its basic substituents. Table salt, sodium chloride, dissolves in water to form sodium and chlorine ions. Sugar dissolves in water to give little individual molecules of glucose and fructose.

However, that's not the whole picture: there's also another category "solutions" known as colloids. Colloids are typically very fine particles of some sort or another that are small enough that the particles can float around without falling out of solution due to gravitational forces, even if the basic substituents that make up the colloid do not dissolve into the parent liquid. A classic example of this is milk-- little globs of milk protein float around the whey in a suspension, repelled by negative charges created by amino acids at the surface of the protein. A

Here, the inventors have made very small particles of silica, about 100 nm in diameter. The silica particles stay suspended in the liquid because of their small size and repulsive forces at their surfaces. They use this suspension to spray onto stuff to obtain the protective coating after the liquid evaporates. This is just like how spray paint leaves behind a thin film of paint.

This sort of technology using colloids has been around for a very long time, though. I'm not exactly sure what these Germans are doing that makes it totally revolutionary, although I suspect no one has really thought of spraying silica onto food, though. Yecch.
posted by beepbeepboopboop at 12:01 PM on February 3, 2010 [5 favorites]


SiO2 is sand people
The Sand People are easily startled, but they will soon be back, and in greater numbers.
posted by Babblesort at 12:02 PM on February 3, 2010 [23 favorites]


Is this made from that unobtanium stuff I've been hearing so much about?
posted by electroboy at 12:12 PM on February 3, 2010


SiO2 is sand people, not asbestos...
Sand + water = mud...
Sand + ethanol = alcoholic mud...


These are common-sense and pervasive opinions on the matter. I hear them a lot. And, from a certain point of view, they have some logic. Siliones and silicas aren't usually that dangerous. They're all about us in the form of dirt and rocks.

Unfortunately nano-particles don't behave the same way macroparticles in living tissue. This isn't about the relatively inert chemistry of silica, it's about the activity of really small particles. The comparison to asbestos is apt. There's growing concern that nano-particles are very biologically active and can cause all kinds of biochemical upset. We don't see this yet because nanotech is not in common use, but the worry is that these could easily become the new asbestos.

For the detail minded, there's more info in this presentation.
posted by bonehead at 12:13 PM on February 3, 2010 [1 favorite]


Good news for the Germans. Now they can coat the forests, and they won't have to keep scrubbing those trees by hand.
posted by StickyCarpet at 12:24 PM on February 3, 2010 [1 favorite]


I look forward to cleaning my living room with a garden hose.
posted by rocket88 at 12:26 PM on February 3, 2010 [1 favorite]


From Skeptic's helpful link we can find some useful facts.

The product is a sol-gel. The precursor for the sol-gel is chosen from alkyltriethoxysilane and/or aminopropyltriethoxysilane. Up to 20% of the precursor (by weight) can be a mixture of the metal oxides Al2O3, TiO2, ZrO2, MgO, and/or V2O5.

To improve the antimicrobial and fungicidal effects, various compounds can be added to the SiO2 matrix. There's a laundry list of possible additives. The patent claims that the film itself has some antimicrobial effect through an ion exchange process involving Si2+ ions.

After that it starts going all organic chemistry on me and between that and not being a native German speaker I kind of lose the thread. There's some stuff about functionalizing the solvent (which is where the talk of alcohol comes in) and adding chitosan or chitosan derivatives.

Here's how to make the basic version:

Mix 100ml tetraethoxysilane, 400ml water, 200ml .01M hydrochloric acid at 20ºC. Stir continuously for 5 hours. That yields a watery SiO2 sol-gel of about 4.5% SiO2 with a particle size of about 6nm.
posted by jedicus at 12:30 PM on February 3, 2010 [4 favorites]


The particles of sand we're talking about are 300 times smaller than a red blood cell.

Then it's not sand.

There is a lot of confusion going on and I suspect a good deal of it is due to terminology and how purposefully vague they are being. Sand is a grain size, not a composition. Most sand in nature ends up being quartz, which is SiO2, because quartz is very resilient. SiO2 is also what makes glass, but when it is glass it has no uniform crystalline structure. Quartz does.

The sand grain size is coarse enough that it will not form mud in water, and so when it dries it will not cake. Even the finest sand does a poor job of caking after drying from water. Like Balisong said, SiO2 isn't soluble in water or alcohol at surface conditions.

Based on the fact that the stuff they're using is incredibly small, it is not actually sand. And the quote up at the top of the thread is that they 'extract molecules of SiO2'. They've broken sand down, likely through dissolution in an acid. Hydrofluoric acid is good for that. But it's not so good for people. I obviously don't know what they've done or how they've managed to reconstitute the SiO2 into glass, but I'm interested to.
posted by six-or-six-thirty at 12:32 PM on February 3, 2010


As a materials science guy who... participates in a bit of research in nano-SiO2 ... I'd be interested to see how they get this to dry without pores. I would imagine most normal nano-SiO2 sprays would create a sort of silica gel, not a tightly bonded nanocrystalline silica. Perhaps it doesn't need to be. At any rate I'll be spraying this on my skin as soon as I can buy it at walmart.
posted by nutate at 12:34 PM on February 3, 2010


Sounds like another 'Moller' to me.
posted by numberstation at 12:37 PM on February 3, 2010


i may never have to shower again! I wonder how this plays against all the petroleum based friction-free surfaces?
posted by mrmod at 12:55 PM on February 3, 2010


4.5% SiO2 with a particle size of about 6nm

That's definitely in the range of concern for nano-particulate behaviour. The chitosan is an interesting addition---it's a molecular glue at that size. That's probably how they propose to get the particles to stick to surfaces, glue them on with chitin.
posted by bonehead at 1:00 PM on February 3, 2010


chitin -- like bug exoskeleton?
posted by boo_radley at 1:29 PM on February 3, 2010


They'll need to get Bowie to license The Glass Spider for their jingle.
posted by Babblesort at 1:34 PM on February 3, 2010


Anybody else flashing on the sand wraiths from Wizard, or is that just me?
posted by kipmanley at 1:41 PM on February 3, 2010


Here are more patents and patent applications by Schwindt and the Stiftung Nano Innovations (it's a Swiss foundation, BTW, the oldest tax avoidance trick in the book).
posted by Skeptic at 1:47 PM on February 3, 2010


Maybe it's "powered" by dowsing rods too.
posted by fontophilic at 1:59 PM on February 3, 2010


Hmm, alcohol and incredibly fine particulate matter? I wonder how flammable this stuff will be coming out of the can.

Not for any particular or nefarious reason, mind you. Just curious.

I swear.
posted by quin at 2:00 PM on February 3, 2010 [1 favorite]


"Filthiness repelling surfaces" has a ring to it
posted by rh2 at 2:08 PM on February 3, 2010


Hmm, alcohol and incredibly fine particulate matter? I wonder how flammable this stuff will be coming out of the can.

SiO2 isn't going to combine with oxygen.
posted by DU at 2:21 PM on February 3, 2010


Pepsi clear?
posted by birdsquared at 7:33 PM on February 3, 2010


I too work on nano-silica and related materials. As far as I can see (reading the PCT through the lens of my very rusty German), they basically just claim spray-on silicone caulking. They use a silicon/silicone precursor (TEOS, PTMS, glymo or whatever), a catalyst, a surfactant to form the film and improve wetting, and a chitosan or some other related agent to get non-newtonian properties for the film characteristics they want. I'd be very surprised if the PCT, or my understanding of it, survives examination and/or subsequent challenges, but I could be missing something major.
They claim the film is 'breathable' which implies it is not fully dense, but rather the pores are small enough to exclude liquids while allowing gas exchange. That would be typical of a xerogel formed from these sort of precursors.
posted by overyield at 11:06 PM on February 3, 2010 [1 favorite]


It's a fairly standard press release. The inventors have by the sounds of it come up with some sort of novel coating technology which has non-stick properties. What they are most likely ddoing is looking for investment to develop it further. Their website is full of similar press releases, full of buzzwords, designed to get as much mainstream publicity as possible and it seems to be working.
posted by bap98189 at 2:19 AM on February 4, 2010


I was unaware that we had general problems with nanoparticles (aware of problems with particular nanoparticles? yes), so that's good to know. Thanks for the details, bonehead. I still wonder about the quantities involved for a consumer using products sprayed with glass (as opposed to someone who's actually applying the glass themselves).

babblesort, explosion (re: sand people): Calm down, I just left out that comma man.
posted by ErWenn at 9:44 AM on February 4, 2010


There are no federal regulations in either Canada or the US specific to general nano-particle products as of yet. The human and ecotoxicology is still in flux. So it's not (yet) on the political radar. Lots of people are concerned about nano-toxicology though---look at any issue of Environmental Toxicology and Chemistry for the past few years. A large fraction of papers now are on nano-particle toxicology.
posted by bonehead at 12:02 PM on February 4, 2010


although I suspect no one has really thought of spraying silica onto food, though. Yecch.

Let me disabuse you of your suspicions: NANOSILICA-BASED FOOD CONTACT SANITIZER

There are no federal regulations in either Canada or the US specific to general nano-particle products as of yet.

The EPA has released "significant new use rules" for two nanomaterials. Silica is one of them. If it weren't for the snow in DC and the federal government shutdown, they would likely have done a lot more on Friday, by rethinking the 'distinct molecular identity' approach for new chemical substance regulation.
posted by anotherpanacea at 12:25 PM on February 8, 2010


Great comment! I had no idea that things were moving this quickly in the US!
posted by bonehead at 2:55 PM on February 8, 2010


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