dat surface tension. so hydrophobic.

He's wrong though. I've seen materials more dense than water float due to a surface coating when I watched some videos on newer hydrophobic coatings years back. It's not the first time by far, they must not have even googled it before making their claim....here's just one....
http://www.rsc.org/chemistryworld/News/2009/March/17030902.asp
Pretty sure that copper and silver are both heavier/more dense than water, and they made a working 'raft' out of coper/silver mesh back in 09.

I'd hate to work with this stuff. Just watching a video of it is infuriating. I want to "see" it but I can't.

This hydrophobic stuff is great for experiments and wow factor but I am still confused at the actual application.

I know it wouldn't have come this far without application but its not like I hear...because of its hydrophobic coating...blah blah blah...pay me more money.

I think some of the new waterproof phones might be using the coatings as one level of protection against water intrusion. Anything in a marine environment could also benefit.

I really doubt this would be considered safe enough to put into something for consumer production like a cell phone. It's made of carbon nanotubes. Those get into the air, and it's very, very toxic to breathe. It is like needles stabbing and slicing through your cellular membranes. There are some real concerns about the long-term safety of CNT. I would feel very unsafe having to work with it every day.

I was not talking about Vantablack in my comments. I was talking about other, older hydrophobic coatings.

Also, I'm fairly sure they bond the nanotubes with something to make them stick and stay in place. Pure nanotubes are just a powder, they would not act like paint. Nanotubes are not a new discovery and have been used in consumer products already, mostly electronics, google it.

Right, they've been used in products that the consumer has no way of accessing without destroying said product. A paint-like application wouldn't be something I would trust to stay applied to the surface. You've seen paint rub off of objects, right? A fine powder is going to stay better than paint over time? You gonna let your baby put it in its mouth?

There have been studies dating back to 2005 or so outlining the possible dangers of these substances, yet we still don't really know all there is to know about it. I'm not so quick to trust that something like that would be safe.

But but thanks for correcting my misinterpretation about the hydrophobic thing.

Try looking up powder coating...it's WAY stronger and tougher than paint, which is also highly toxic and chips off far easier. I'm not certain the Vantablack nanotubes are applied that way, but I'm certain that your hypothesis that powder coatings are not as tough or as sealed as paint is wrong. EDIT: Powder coating is going to stay better than paint over time. Yes.
You gonna let your baby suck on paint chips? Did your parents let you? ;-)

Yes, I don't disagree that in powder form nanotubes can get into everything and may be toxic....but in a sealed coating, they are not loose. Be afraid if you wish, but your fear is misplaced IMO. The only one's in danger of breathing the powder are factory workers.

Okay first off, powdercoating is different. It's a powder that is closer to glass than paint, and it's cured in an oven which melts it onto the surface. Vantablack is grown on a surface and they recommend it is never used in an application where skin contact is involved as it would be unsafe. The sprayable paint version uses another form of carbon nanotubes in a different structure, which is considered "safer," but there's not enough data on it for me to trust it. They also make no mention of it being "sealed" as you claim.

You can if you want. Lead paint was once considered safe, as was asbestos, and aspartame, and cigarettes (at least publicly). Go for it. But we won't agree.

OK, as I said, I don't know exactly how Vantablack is applied, but nanotubes could easily be incorporated in powder coatings and be totally sealed in the coating.
If Vantablack is grown on the surface, it should be even more 'attached' at the molecular level to that surface, shouldn't it? Once the loose powder was cleaned off, that seems like it would be much better than paint at sticking permanently, no?
A sprayable paint version would have to be mixed with a liquid that makes it sprayable and makes it stick, so I would expect it to be 'sealed' in that liquid once it cures, just like any pigment in any paint. Also, clear coats could seal it in if that's not the case, at least as good as any other toxic paint. EDIT: Since nanofibers can withstand high temperatures, they could even bake on a clear powder coating that's WAY tougher than clear coat to seal it if needed.
Most paints use highly toxic chemicals too. Just because there's no lead doesn't mean it's non toxic....in fact, it might be MORE toxic, just not in the same "brain damaging" way.

I have actually personally worked with nanotubes. I had a friend I worked with that had a carbon fiber business that did dozens of experiments with it for multiple projects, including a carbon fiber bullet and machine-able solid carbon blocks. He'll probably be the one to watch to see how dangerous they are, he rarely used any type of protection and I'm sure he inhaled multiple grams worth of nanotubes in his time, and has them imbedded in his skin all over his body. All of his products used resin to liquefy and harden the nanotubes into the shapes he wanted, so in the end products, it was "sealed" into a non-powder form, but not during production.

Clearcoating this stuff would remove its blacker-than-black properties. It would then start to reflect light. At which point, why would you favor this expensive shit over regular paint? I haven't seen details on how the sprayable Vantablack is applied, but if it were mixed into a liquid for application, it would have the same problem, unless, somehow, the surface of the hardened material were burnt away, evaporated off, or chemically reduced so that the carbon material could protrude from the substrate, that may allow the light absorption properties to persist. But I don't know how they accomplish that, other than they say it's a complex process that requires a specialist. I still wouldn't try brushing up against it, just like I wouldn't try sitting there inhaling paint fumes after painting a car. There's a reason precautions are taken in that process as well. I just know that something small and damaging enough to burst cell membranes sounds like something I wouldn't want in a product I'm handling with direct contact with my skin, or with any remote possibility of it rubbing off and getting into the air.

Probably, but there are all kinds of clear coating. They could develop one with minimal reflective properties and minimal absorptive properties, but you're right, even then it would decrease the effectiveness, but maybe not so much that it would lose it's usefulness.

I think in most applications, the nano fibers are encased in resins or other chemicals that cause them to clump together, making them much safer (note that I don't say "making them safe").
In pure powder form, yeah, they're a bit scary to have something that can float in air that can also burst cell walls. I always used a facemask and gloves when I was in his "lab", and even so I'm sure I was contaminated. Now I wish I had worn a full anti-contamination suit.