Could be the spectrum that its tested under. Maybe the 99.6% is visible light and the 98% is all energy from sun. If that's the case, the 98% is much more impressive.
Anish Kapoor & the creators of Vantablack for hoarding the material and for generally being rotters.
Dupont for the imprisonment of tech consultant Walter Liew for espionage, after he stole and sold blueprints for their secret titanium white process for over $30million.
T-Mobile & its parent company Deutsche Telekom for claiming magenta as their own and suing small businesses for using it.
Scientists at ISIS Neutron and Muon Source who are in the process of investigating polar bear fur, insect scales and fathers for industrial and commercial applications.
3M for their ownership of Canary Yellow.
Daniel Smith, for buying up the last reserves of quinacridone Gold pigment in the world, so that only they would be able to sell it to artists.
Cows are fairly peaceful animals that naturally live in a herd and have been domesticated for thousands of years (people can get killed by cows, but it's rare).
Bears are huge ferocious animals that typically live solitary lives and will kill you and your entire family while hardly breaking a sweat.
Keeping polar bears "like cows" sounds like some good comedy sketch material.
I know this is such a small microcosm of the world, but I really love to see, just once in a while, that someone with power uses their power for the greater good and not for selfish benefit (realistically "we won't sell to Kapoor" is a marketing spin but it's still a risk and a strong statement).
> In response, UK-based artist Stuart Semple created a pigment that he claimed to be the world's "pinkest pink" and made it available to purchase on his website for "everyone but Anish Kapoor".
Can I get in on that action? I don't understand why instrument cluster bezels are universally chromed but I hate it and my eyes hate it and I'd really like to look at my gauges without getting blinded.
Hah, yep, same situation on both my Ford vehicles.
I think I’ll end up removing the trim, masking the pieces I dont want to paint, and then hitting the chrome with Plastidip spray. It’s an aerosol can that contains a rubberized coating. It comes out looking like a matte finish paint but it can be peeled off of most surfaces so it’s not permanent.
I tried it. It's not that black at all. My regular black T-shirt was blacker than a piece of cardboard I painted with Black 3.0. Super disappointing, to say the least.
Your T-shirt's a 3d structure with microfibers. I'm not surprised it was able to be more black than a hard surface: fabric's actually a really good way to make an intense black.
The Culture Hustle blacks are also matte, which is very much a limiting factor (and part of the concept). I find if you're willing to accept highlights, super gloss black is way better at being super black everywhere that isn't a highlight. At that point you're trying to get the most localized highlight as possible, to get it out of the way so everywhere else can look blacker.
I wonder how well this holds up to dust, pollen, UV, etc. At some point is the difference negligible? Every white commercial roof I've ever seen is much less white after some time passes.
Someone needs to compile a list of all this fringe tech that I see popping up in my feeds, almost daily now. I know there are techpress blogs that pump out articles like this, but there doesn't seem to be an authoritative compendium of such tech anywhere on the net. I could curate this by hand with 3 hours of free time and some Red Bull I suppose.
The reason I want this is because we seem to be swimming in innovation, but nobody to aggregate and make sense of it all, and `join-the-dots` of all this tech so we can make even bigger leaps with it. Also: A lot of these articles are great, but too quickly shoved into people's bookmarks and forgotten about, without any real action taken on them. Put simply: we are addicted to innovation, but with little action taken on this innovation!!
Such a good idea!
There's so much stuff being invented, some of it outright insane and yet it's almost impossible to find anything, unless you are very knowledgeable in a particular field.
For instance,I've been subscribing to materialdistrict.com for years and some materials they showcase are simply mind boggling.
I agree. Such a compendium would be great and more so if that would be the only place where we can get the information about inventions and innovations.
This reminds me of the 2.8kg pyramid which sits atop the Washington Monument. At the time it was cast, it was the largest single casting of an exotic metal which cost more than silver, known to you and I as Aluminium.
You need machine tools capable of tight tolerances and quality metals/alloys to make useable (for work) steam engines. The Egyptians, Greeks, Romans, Abbasid, Persians, Europeans, etc all lacked these, thus no usable steam engines in antiquity/Middle Ages. Usable engines followed consistent quality metal production and machine tools pretty closely, it’s not like older people were just stupid, they didn’t have the technology necessary to create steam engines capable of real work.
It’s like asking “Why wasn’t there a chess engine as good as stockfish for the PDP-11?” It simply wasn’t possible with the technology in 1970.
Good point regarding tooling, metal, and tolerances.
But in this hypothetical timeline they would’ve hand-made the first leaky and inefficient engine if someone with some clout had the idea for a piston back then.
These people didn’t blink at moving mountains to build burial crypts, so it’s conceivable that they might’ve experimented with steam if that notion struck, say, the pharaoh.
Smil’s book about Making the 20th Century has some good context for this type of discussion. Highly recommended if interested in how technical leaps happen.
That's a conventional response with a lot of merit to it.
But then I watch Clickspring recreating the Antikythera mechanism, and I wonder.
Yes, there is a big leap between what is effectively clockwork and, say, making a pressure boiler. But I wonder: if Francis Bacon had been a student of Euclid and derived the scientific method in 3rd century BC Alexandria, and Rome had been better governed, devoting more energy to science and less to war, speed-walking the tech tree 1500 years early isn't impossible to contemplate.
Really shows the value of protecting an enlightened state with a strong military.
Science = long-term benefit, military = survival right now.
I remember playing Master of Orion 2 with a pure science focus and getting my ass whipped every time.
Then I realised that a good long term strategy needs to work around a good short-term strategy which enjoys priority. I switched to population and production focused games, and suddenly the “Impossible” AI was too easy.
Romans had copper and that would be enough to run the Empire using the telegraph. They just didn't know about the electricity and how to make a voltaic pile in particular even though they had the sufficient technology.
Zink was used by ancient Greeks and Romans in a brass alloy. Zink and copper are interchangeable in a crystal structure of brass, and are inseparable because of that. Obviously, brass is useless in voltac pile because of copper in it.
I am not that sure about vinegar as a medium. I beleive it will lead to low voltage and weak power, rendering the pile useless for long distance transmission.
The same applies to copper wire. You need steel to draw copper to make wire, otherwise wires will be short, need to be soldered and become ineffective for long distance.
Also, telegraph lines are too easy to sabotage. Fire signals are much more reliable to rule ancient empire.
This is nothing new. You are just now hearing more about it because of how journalism is being done online. There have always been lots of revolutionary things happening in labs. They are rarely ever practical, or if they are it will take decades to bring to market. How many dozens of new battery techs are announced as being "better than lithium ion" only to disappear once everyone realized how impractical they are. Such announcements were once confined to scientific journals and trade mags. Now the great algorithm makes them daily news bulletins right beside the Kardashian latest puppy video.
I researched this a few weeks ago and commented here[1]. I got a reply from someone with firsthand knowledge of the work. I love HN for that kind of stuff!
Your point clearly has merit in many cases, but paint seems almost the epitome of practicality. Assuming that it could be mass producible at a price similar to premium house paints I can't see the problem in bringing this to market.
And from the article:
> In the US, New York has recently coated more than 10 million sq ft of rooftops white. The state of California has already updated building codes to promote cool roofs.
> Assuming that it could be mass producible at a price similar to premium house paints I can't see the problem in bringing this to market.
Unfortunately, that's the whole point of this little discussion, right? GP is saying how many things like this, yes, seem like they have merit, but at the end of the day can't be produced practically outside of a lab.
There are a lot of practicality/implementation concerns to paint other than what color it is. Just as many if not more than there are for battery technologies.
Does the paint stick to the surface you want to paint, how is it applied, what is the coverage, is it durable, does it repel contaminants, can it withstand the environmental conditions, is it chemically compatible with the surface, it is chemically a concern for the other items/humans/animals that may come in contact with, can it be produced at scale, does it (and it's vehicle for application) meet regulatory standards? etc...
They used standard acrylic paint manufacture techniques, just substituting barium sulfate for the usually-used white pigment titanium dioxide. So most such questions should be answered simply by looking at previous experience with existing white acrylic paint.
Other factors include how it ages, w.r.t. thermal emittance (emissivity) and solar reflectance (SRI). See the "3 years" columns here:
https://coolroofs.org/directory
Many products drop by several % after a few years.
one thing i’ve learned from doing little home improvement projects over the past few years is that paint is a 2-part product, primer and topcoat, and neither should be skipped if you want good results. generally speaking, primer sticks and seals while topcoat colors and protects. this isn’t made obvious in any way to the novice, and big box store workers seem as ignorant about it as anyone.
Depending on the application, the primer coats can fulfill a couple other requirements as well:
If you want a really smooth topcoat, you usually want to sand past what you can reasonably/economically/effectively do on the substrate. Some primers are formulated to sand nicely to a powder (as opposed to balling up in clumps on the paper). You'll see this spraying higher quality paint grade work. You have to have a decent surface before you prime, but the primer can really smooth it out for the topcoat.
If you're finishing pine with knots in it, you'll want a primer that will seal the knots, otherwise the pitch will eventually bleed through and discolor the topcoat. Shellac excels at this.
Shellac is also outstanding as a sanding sealer. You can use that in a couple of ways: to fill the pores in the wood so they don't get full of sanding dust (which can be key if you have inlay of strongly contrasting woods), or to stiffen the fibers of softer woods so you can get a better/smoother sanded surface for the next steps in the finishing schedule.
Shellac is also often used as a barrier coat between otherwise incompatible finishes or when you have a relatively fragile stain layer. If you're putting an oil based finish over an oil based stain, you run the risk of picking up the stain as you apply the topcoat, especially if you're brushing or wiping the topcoat. Because the solvent in shellac is alcohol, you can pretty freely brush it over oil or water based stains without risking a disaster.
And yes, I do use primers other than shellac from time to time if I have a specific need, but dewaxed shellac is compatible with basically everything, so I always have a can around.
N.B. I'm not a professional finisher. Don't take my word on any of this; test your prep and finishing schedule on scrap!
> “If you're finishing pine with knots in it, you'll want a primer that will seal the knots, otherwise the pitch will eventually bleed through and discolor the topcoat. Shellac excels at this.”
yes, i learned this the hard way, albeit on a simple set of wall shelves as cat stairs that i can easily fix eventually with shellac and another topcoat (when i get around to it).
The big box stores employees at the paint counter seem as ignorant as a novice about the vagaries of application most likely because they themselves are novices. They may know quite a bit about colors and matching and how to work the mixing machines, but they probably don't have much more experience painting than the average homeowner. That knowledge comes more from doing, whether its a handful of projects as a homeowner, or regularly as a professional.
IMO, the stores could do better about offering basic information about this, about when one would need a primer, or just a topcoat, what kinds of paint bases are appropriate for what applications, what kinds of application methods are appropriate, etc. Instead, the response of the big box stores seems to be to skip the question entirely with combined products, e.g. "paint and primer in one".
yes, there's no experience or incentive for better knowledge in big box stores unfortunately. i've moved on to buying from a local paint specialty store, which is owned by a family that i believe is/was in the construction/painting business. they cater mainly to contractors but also sell to the wider public.
oh, and yeah, paint and primer in one does neither job very well.
Yep, been there too: paint is really something where you want to avoid the big shop and goes to speciality stores instead (paint peeling from the wall? Color changing after a year? Done and done --> switched to a dedicated paint store == no more issues, the paint itself is more expensive sure but the result is stable)
Actually that last bit there seems to be more important to me than the actual tech here. So without this tech people are painting rooftops white. And I'm guessing that's already like a 90% reflectivity? -- So there's really nothing to wait for if you want to cool your house. Just buy... exterior white paint.
If you wanted to wait for this specific product, that's fine, but that's almost like waiting for 26% efficient solar panels instead of ~23% we already have (even though most production panels are 18% - 22%)...
And actually this is also one of those things that also helps beat Tesla Solar roof - get a white paint - THEN add bifacial solar panels. So the Tesla roof panels is actually worse for your overall cooling than regular panels now.
The whole point of the discussed paper and of their patent applications is that normal white paint is not good enough to cool something exposed to solar light.
The white-painted object will heat less than when painted in another color, but it will heat anyway.
The white paints described in the paper and in the patent applications, which use either barium sulfate or calcium carbonate instead of the normal titanium white pigment, actually cool the painted object, even in strong solar light.
I understand that there are scientific discoveries which are worth the investment money or otherwise. But I would prefer the great algo to pick these up for me rather than which star admires who.
I think ultimately what you want is some measure of say it's practicality / viability to really make change?
I think the catch is that if you really knew that... you'd be out making an insane amount of money as you'd be able to pick and choose winners / make them work ;)
I'm reminded of the old TV series "Connections" where lots of individual innovations are cobbled together over surprisingly long periods of time to really have an impact. Mostly... it seemed like a combo of inspiration and happenstance when someone strung them together.
I think part of they problem is that whoever invented this paint is going to want a massive premium for its sale. So it'll get some niche industry use until the patent expires and people start painting their desert roofs with it, or whatever else. Apply to this virtually every technical innovation that is iterative. Fundamental breakthroughs allow for a shakeup of the incumbents, iterative ones don't, due to the archaic IP laws that only serve to stifle innovation. I think a better solution would be arbitrated profit sharing as a percentage of the cost of the product proportional to the value added with no requirement for the consent of the rights owner. Decay the percentage to 0 over the same timespan as current patents.
This is a very insightful comment. Perhaps you are aware, but some economists have designed mechanisms to "split the difference" in a manner similar to what you describe:
I’m pretty sure this is developed and patented by Purdue University (or perhaps a partnership). They don’t really try to extract extreme fees for usage.
Or get rid of patents entirely and let innovation and copying happen freely. I already ditched all my physical startup ideas because China could clone any of them in half a day and I think it's fair: they have superior / more efficient manufacturing available.
Similarly I don't see why discovering something should force everyone else on the planet to give you money.
In this particular case, thought, the article claims they won't be patent trolls and this paint should be cheaply available.
What sources are you using for fringe tech that you would compile from? Even a list would go a long way to expanding mine and other peoples concepts of innovation.
The field you're looking for is called "tech transfer" - many universities have technology transfer offices that help research connect from a lab to industry, usually enriching researchers through the sale of patents or consulting contracts.
I don't know of any compendium on the web, but if someone were looking to get started there is a field to dig into where people do this kind of work full time. It's essentially a two-sided market making process of curating useful innovations and building up a sales function to close deals.
Completely agree. I'm working on something to solve this problem and I'd love chat more about your thoughts on this. Contact info in profile if you're interested!
In The Chip, T. R. Reid talks about how Kilby and Noyce (inventors of the integrated circuit) spent time reading through new patent applications every day/week. As programmers, we spend a lot of time reading blog posts, but it's possible to take it further than that. For a couple years I attended a database reading group every Friday at a local university, where each week we would discuss a paper someone was interested in. You may also have alumni access to interesting journals. Or A Morning Paper[0] is a more Readers Digest approach. It takes some intentional work, but it's fun and you learn a lot.
>The reason I want this is because we seem to be swimming in innovation, but nobody to aggregate and make sense of it all, and `join-the-dots` of all this tech so we can make even bigger leaps with it.
There is. It's called "the market". Each one of those innovative ideas gets tested by their inventors and backers against real world use-cases. Nothing validates an idea or innovation more than someone writing a check to buy it.
On their own though, right? That's not what was being asked. They wanted someway to track things that would work really well together and bring bigger benefits than things could on their own.
Yeah. When I ran a startup, you look for customers, but you also look at partnerships all the time to complement whatever you're doing. Sometimes the partnership finds you, and sometimes you find the partnership. You attend tradeshows and conferences. Sometimes your customers will point you at another company you should work with. That's all part of the market. People behind innovative technologies (inventors, and investors) are constantly looking to find ways for their tech to gain traction.
>They wanted someway to track things that would work really well together and bring bigger benefits than things could on their own.
OP is advocating for a top-down system where they can get a list of innovative technologies and just put them together like lego. It doesn't work that way. It's why a top-down command economy with a central authority doesn't work. There's a lot of trial and error (and failure) that happens at the bottom level and from the top, you just don't know what ultimately is worth expanding effort on and what is a waste of time. Any decision you make about what should go with what is going to be wrong. That's why the market is so powerful for innovation.
It dissipates as heat into the paint and it's substrate, I assume. At least that's what I always thought we wore dark clothes in winter and bright ones in summer.
Some black paints/surfaces for solar heating applications are the opposite of the white paint in this thread: absorb strongly in visual and near IR, but only weakly in far IR (and so have low thermal emissivity at those wavelengths.)
I would expect it's twofold. This paint acts like a "diffuse mirror" so doesn't create any bright spots like specular reflection. This is great particularly in cities where every building would become a giant mirror. On the other hand a mirror finish is harder to achieve on rough surfaces that the paint would presumably be used on.
Mirrors don't have to reflect very much, they have to reflect as a picture. That's why one-way mirrors work — people generally don't notice that the light mirrored is much less than 100%. White paint is free to reflect the photons in any direction, so that >98% is a harsher requirement on the share of incoming photons, but a laxer requirement on the photons' direction.
Some mirrors can reflect a lot more light even if in narrower wavelength ranges. But that only makes the matters worse from a practical human perspective, when trying to use them on large surfaces outside. It would feel like staring into the Sun far too often.
Aluminium coating (most mirrors) only reflects between 80% to 90%. It reflects light in single direction. White paper reflects more, but scatters light in several directions.
Mirrors that are a cheaper coating on glass or metal can be in the 95% range without too much effort. If you don't care about actually forming an image with a mirror, it can be quite cheap, e.g., plain aluminum (with whatever oxide forms on its surface) or aluminized mylar film.
I assume this could be useful to shield something in space with extremely specific temperature tolerances.
I'm not sure about the suggestion that people are going to paint their roofs with it. People already have the opportunity to paint their roofs with cheap white paint which would provide nearly all the benefits this would, and still choose not to do it.
> Commercially available white paints reflect between 80% and 90% of sunlight, according to lead researcher Prof Xiulin Ruan from Purdue, in West Lafayette, Indiana. "It's a big deal, because every 1% of reflectance you get translates to 10 watts per metre squared less heat from the Sun," he explained.
Yes, sure, but if you painted just two roofs white with regular paint, you're already doing much better than painting a single roof white with super-fancy paint.
White roofs don’t look great which is why I think they’re largely relegated to commercial buildings instead of residential ones. They get dirty fast, are super bright and don’t fit with the traditional look for houses. On commercial flat top roofs they are hidden so it doesn’t matter if they’re blindingly bright or stained because they’re not visible.
It likely rains enough in humid environments to make dust a non issue. Both because you get vastly less dust in the air and because it washes away most dust that does show up as long as the roof has a significant slant to it.
However you don’t need white to see significant benefit over a black roof, even just green helps.
They show any dirt really clearly so for houses it’s a crummy choice because it’s not hidden on out of view (on most houses, if it’s a modern house with a flat roof you could potentially use a flat white painted roof) which means cleaning a lot.
It's bad for wet environments and snowy ones. You need to be super vigilant about inspection and maintenance if you have a flat roof where I live in northern U.S. While two feet of snow on the roof will provide a small amount of insulation, every material in contact with it needs to be rubberized or sealed every couple of years or both.
Shovelling your roof with a flexible waterproof membrane can lead to gouges which defeat the impermeability. And one small leak can go unnoticed until it has seeped into the visible part of the house and rotted rafters and supporting timbers. Drainage on flat roofs get clogged and need to be cleaned or you end up with standing water.
A sloped metal roof will last for 30+ years without any maintenance. A flat roof of any type will require several maintenance operations a year and last half that unless you have a commercial tar and gravel roof which is heavy and imposes additional load bearing requirements on the structure.
I'm recalling a technology from 70s Southern California: low-slope, tar paper for water seal, half-centimeter fragments of broken light-colored rock scattered on top. Dust falls through the gaps onto the tarpaper.
One downside being that after a heavy rain, some fraction of the gravel makes its way down from the roof.
What looks great and what is not significantly affected by what are you used to see. In the place I've ground up galvanized steel roofing was common and I think it looks fine. But someone who used to dark roofs likely would tell that galvanized steel looks ugly.
If you look at old architecture in rural Georgia and Alabama. Houses are on rocks raised above the ground (air circulates underneath), 10 ft ceilings, a huge attic fan to pull cool air in in the evening, tall trees planted next to the house for shade (we have 4 pecan trees), and reflective tin roofs (if still shiny). This helped significantly to cooling in the summer. Winters aren't cold enough to warrant more than a fireplace in the common area. We have an old farm house built in the 1920's...the old original part of the house doesn't get uncomfortable until the temperatures outside get above 100. A newer part of the house with standard 9ft ceilings built in the 70's gets very warm and uncomfortable.
The same kind of ideas were present in bungalows in British India and other parts of Asia.
In general I think a lot of energy savings can be realized by accommodating buildings to the prevailing climate, and using passive means of heating and cooling.
Wide eaves help as well to keep summer sun off windows and to provide a place for a porch. A gentle rain on a tin roof is a sure ticket to sleep; a strong one not so much.
I'd never thought about ceiling height - that makes a lot of sense.
Well designed buildings for passive cooling/heating in the higher latitudes can also take advantage of wide eaves. Since the sun is lower in the sky during winter you can design a home with eaves that block the summer midday intensity but allow sunlight to flood in throughout the winter with some careful calculations and site placement. Houses built to suit their location can slash the amount of energy required to regulate the temperature.
Corrugated material could provide a white surface to the mid-day sun in the summer and a black surface to the mid-day sun in the winter. Of course you'd need to take latitude and roof slope into your calculations but I bet if you made the materials in 10-deg increments you could get something "good enough" for most use cases. Or you could just make the material change color based on temperature.
This is all known science but getting it cheap enough to be used as roofing is the trick.
Oh, nice, a lenticular roof. Make it show white from summer sun angle, black from winter sun angle, tile roof images from ground level, and a "Pull Up" sign for aircraft overhead.
I'm really curious about the energy savings that roof mounted solar provides (not including electricity that the panels produce).
In the summer, they shade the roof keeping it cooler.
In the winter, they provide an additional ventilation area that allows heat to escape without melting snow (thus mitigating risk of ice dams). Even a snow covered solar panel provides a benefit.
Disappointingly few of them, still. It's always depressing to fly over an area and see nothing but black rooftops, devoid of anything but HVAC equipment. I know green roofs have engineering issues but I hope one day I will instead look out my airplane window and see a sea of solar panels, small wind turbines, and rooftop gardens.
They said that they have used an acrylic binder, so this white paint should behave like any other acrylic paint, so it should need periodic cleaning.
What is novel is that they have discovered some new method for preparing the barium sulfate pigment and mixing it with the binder, which allows very small pigment particles, possibly having a certain form, and also a very large ratio between the quantities of pigment and binder in the paint.
1. The more common white pigment titanium white is not good for cooling something exposed to sun, because it strongly absorbs ultraviolet light. (Besides generating heat, this ultraviolet absorption also causes photo-chemical reactions that degrade in time the organic paint binders.)
2. So they have chosen barium sulfate, which reflects not only visible light, but also ultraviolet and near infrared.
3. Barium sulfate not only reflects solar light, but it also emits efficiently in the far infrared, which cools the painted surface.
4. Barium sulfate was traditionally considered a worse white pigment, because it has a lower refractive index than other pigments, like titanium white.
5. The Purdue University team has overcome this disadvantage of barium sulfate by designing a manufacturing process for the pigment that not only ensures a very small average pigment particle size but also a broad distribution of the particle sizes, which results in good reflection properties over the entire solar spectrum.
The notion of painting roofs white to increase albedo is an old one (look up "Whitecap", which I was familiar with about 30 years ago). And the practical limit is of behaviour in the environment: dirt, grime, damage (hail, wind, birds, insects, ultraviolet light, etc.). It's unlikely that a "whitest white" substance will also be optimised for those characteristics.
But a durable, easily-cleaned, reflective surfacing material could prove useful.
It's all but certain that the actual applications for this material won't be as roofing. At least not for standard construction.
Reminds me of “anti-flash white,” developed for bombers during the early years of the cold war. The theory was that the specially formulated white paint would reflect enough of a nuclear explosion’s thermal energy to allow the aircraft to survive the explosion as the bomber departed the scene.
The Wikipedia page does say "The purpose of the colour was to reflect some of the thermal radiation from a nuclear explosion", as far as my experience goes polished metal can still get extremely hot.
A mirror would reflect light directionally, but white paint would seem to be diffuse.
Or said in another way, seeing a laser in a mirror might cause retinal damage, but on a white wall you would just see a dot. (although probably a speckly coherent dot)
The felt sensation of temperature depends not only on the temperature but also on thermal conductivity. With a low conductivity you feel less of a temperature difference to your body temperature. Most stuff in your apartment should have the same temperature, go and touch some metal objects and ceramic tiles or so.
Indeed, a friend of mine who designs playgrounds told me that one of her constraints is for slides not to be oriented such that they heat up too much from the sun.
I wonder how well it reflects in the atmosphere's transparency window?
I've been following news about materials which reflect in this spectrum so much, that they effectively cool their surroundings, but I understand that this paint, while probably less effective, should be much cheaper.
While Vantablack is blacker, it is not all that usable. For example, it can't be used for clothing. IR flock sheet is better for general use: https://www.youtube.com/watch?v=N9VaJKIO1JA
You could probably more easily do this with just a flat surface that you can rotate. Smaller the squares the better uniform distribution you can get but if you don't have those strict requirements then why go super small (e-ink)?
I'm assuming you would have put this on some conductive surface. Otherwise the black side wouldn't be super useful (you'd re-radiate heat back but conduction is better).
You joke but it's interesting to think about what mixing them or mixing their components would do.
Mixing them as-is would ruin the effect of Vantablack. Since carbon nanotubes are black you probably would get a boring grey color with a gloss surface due to barium sulfate.
I'm curious what the effect would be if you coated Vantablack with barium sulfate. A highly reflective surface with an extreme black paint underneath.
Though black surfaces radiate energy more easily due to higher emissivity, and white radiate less due to low emissivity. So the benefit may be less than you think.
Notably, the benefit may be "less" than expected but for all intents and purposes any building or vehicle painted black will be consistently warmer than the equivalent in white. Unless your item is built for purpose it's highly unlikely painting something black will make a visible difference in the cooling rate compared to the white one, at least not in conditions that might be relevant for our discussion.
Won't this rapidly lose reflectively anyway on top of any city building due to soot/dirt? Lowering cost or increasing durability probably matters far more for reflecting sunlight using white paint.
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[ 4.6 ms ] story [ 273 ms ] threadFor sale at: https://www.culturehustleusa.com/
WHY ARE THE COLOUR CRIMINALS BANNED?
Anish Kapoor & the creators of Vantablack for hoarding the material and for generally being rotters.
Dupont for the imprisonment of tech consultant Walter Liew for espionage, after he stole and sold blueprints for their secret titanium white process for over $30million.
T-Mobile & its parent company Deutsche Telekom for claiming magenta as their own and suing small businesses for using it.
Scientists at ISIS Neutron and Muon Source who are in the process of investigating polar bear fur, insect scales and fathers for industrial and commercial applications.
3M for their ownership of Canary Yellow.
Daniel Smith, for buying up the last reserves of quinacridone Gold pigment in the world, so that only they would be able to sell it to artists.
https://www.bloomberg.com/features/2016-stealing-dupont-whit...
https://sandrinemaugy.com/2018/04/30/the-final-batch-of-quin...
Bears are huge ferocious animals that typically live solitary lives and will kill you and your entire family while hardly breaking a sweat.
Keeping polar bears "like cows" sounds like some good comedy sketch material.
Also, injuries and even deaths from dogs are still quite common, and polar bears (and their hypothetical domesticated descendents) are a lot stronger.
https://www.dezeen.com/2017/07/07/anish-kapoor-banned-from-u...
> In response, UK-based artist Stuart Semple created a pigment that he claimed to be the world's "pinkest pink" and made it available to purchase on his website for "everyone but Anish Kapoor".
I love artists.
https://www.instagram.com/p/BOWz73wgj7R/
Q. Can I paint my car / bike etc...
A. NO - 3.0 is quite fragile and will just scratch off, it won’t weather well.
Q. Can I put a topcoat over it then?
A. NO that will destroy the matte effect, and many topcoats (including our COAT) will react with the paint and ruin the finish.
https://culturehustle.com/collections/black/products/black-3... (it's on the right hand side a few scrolls down the page)
I think I’ll end up removing the trim, masking the pieces I dont want to paint, and then hitting the chrome with Plastidip spray. It’s an aerosol can that contains a rubberized coating. It comes out looking like a matte finish paint but it can be peeled off of most surfaces so it’s not permanent.
The Culture Hustle blacks are also matte, which is very much a limiting factor (and part of the concept). I find if you're willing to accept highlights, super gloss black is way better at being super black everywhere that isn't a highlight. At that point you're trying to get the most localized highlight as possible, to get it out of the way so everywhere else can look blacker.
before: https://photos.app.goo.gl/usBMEYDRgykc2bni6
after: https://photos.app.goo.gl/89cyApVzncXWcHYt5 https://photos.app.goo.gl/zxnGMrcUrodM78Lq8
night (really just gone): https://photos.app.goo.gl/La1KNutxn3PhSEAg8
closeup: https://photos.app.goo.gl/uQ3d5oRYtnB3Tfzh8
The reason I want this is because we seem to be swimming in innovation, but nobody to aggregate and make sense of it all, and `join-the-dots` of all this tech so we can make even bigger leaps with it. Also: A lot of these articles are great, but too quickly shoved into people's bookmarks and forgotten about, without any real action taken on them. Put simply: we are addicted to innovation, but with little action taken on this innovation!!
For instance,I've been subscribing to materialdistrict.com for years and some materials they showcase are simply mind boggling.
Think what could have been had we joined those two dots in 2000BC instead of 17-1800 AD.
I should note that their train was of course pulled by slaves and not a locomotive.
It’s like asking “Why wasn’t there a chess engine as good as stockfish for the PDP-11?” It simply wasn’t possible with the technology in 1970.
But in this hypothetical timeline they would’ve hand-made the first leaky and inefficient engine if someone with some clout had the idea for a piston back then.
These people didn’t blink at moving mountains to build burial crypts, so it’s conceivable that they might’ve experimented with steam if that notion struck, say, the pharaoh.
But then I watch Clickspring recreating the Antikythera mechanism, and I wonder.
Yes, there is a big leap between what is effectively clockwork and, say, making a pressure boiler. But I wonder: if Francis Bacon had been a student of Euclid and derived the scientific method in 3rd century BC Alexandria, and Rome had been better governed, devoting more energy to science and less to war, speed-walking the tech tree 1500 years early isn't impossible to contemplate.
Fun to think about anyway!
Science = long-term benefit, military = survival right now.
I remember playing Master of Orion 2 with a pure science focus and getting my ass whipped every time.
Then I realised that a good long term strategy needs to work around a good short-term strategy which enjoys priority. I switched to population and production focused games, and suddenly the “Impossible” AI was too easy.
>You would need pure zink (obtained in ~1750)
https://en.wikipedia.org/wiki/Roman_metallurgy#Types_of_meta...
"By the height of the Roman Empire, metals in use included: silver, zinc, iron, mercury, arsenic, antimony, lead, gold, copper, tin"
>You would need copper wire to implement telegraph
copper is very pliable, so it is easy to make wires.
I am not that sure about vinegar as a medium. I beleive it will lead to low voltage and weak power, rendering the pile useless for long distance transmission.
The same applies to copper wire. You need steel to draw copper to make wire, otherwise wires will be short, need to be soldered and become ineffective for long distance.
Also, telegraph lines are too easy to sabotage. Fire signals are much more reliable to rule ancient empire.
Contact info is in my profile if interested.
[0] https://elidourado.com/blog/notes-on-technology-2020s/
[1] https://news.ycombinator.com/item?id=26040009
And from the article: > In the US, New York has recently coated more than 10 million sq ft of rooftops white. The state of California has already updated building codes to promote cool roofs.
Unfortunately, that's the whole point of this little discussion, right? GP is saying how many things like this, yes, seem like they have merit, but at the end of the day can't be produced practically outside of a lab.
Does the paint stick to the surface you want to paint, how is it applied, what is the coverage, is it durable, does it repel contaminants, can it withstand the environmental conditions, is it chemically compatible with the surface, it is chemically a concern for the other items/humans/animals that may come in contact with, can it be produced at scale, does it (and it's vehicle for application) meet regulatory standards? etc...
Many products drop by several % after a few years.
If you want a really smooth topcoat, you usually want to sand past what you can reasonably/economically/effectively do on the substrate. Some primers are formulated to sand nicely to a powder (as opposed to balling up in clumps on the paper). You'll see this spraying higher quality paint grade work. You have to have a decent surface before you prime, but the primer can really smooth it out for the topcoat.
If you're finishing pine with knots in it, you'll want a primer that will seal the knots, otherwise the pitch will eventually bleed through and discolor the topcoat. Shellac excels at this.
Shellac is also outstanding as a sanding sealer. You can use that in a couple of ways: to fill the pores in the wood so they don't get full of sanding dust (which can be key if you have inlay of strongly contrasting woods), or to stiffen the fibers of softer woods so you can get a better/smoother sanded surface for the next steps in the finishing schedule.
Shellac is also often used as a barrier coat between otherwise incompatible finishes or when you have a relatively fragile stain layer. If you're putting an oil based finish over an oil based stain, you run the risk of picking up the stain as you apply the topcoat, especially if you're brushing or wiping the topcoat. Because the solvent in shellac is alcohol, you can pretty freely brush it over oil or water based stains without risking a disaster.
And yes, I do use primers other than shellac from time to time if I have a specific need, but dewaxed shellac is compatible with basically everything, so I always have a can around.
N.B. I'm not a professional finisher. Don't take my word on any of this; test your prep and finishing schedule on scrap!
yes, i learned this the hard way, albeit on a simple set of wall shelves as cat stairs that i can easily fix eventually with shellac and another topcoat (when i get around to it).
i.e. electroplate > primer > base > mid pearl > clear
IMO, the stores could do better about offering basic information about this, about when one would need a primer, or just a topcoat, what kinds of paint bases are appropriate for what applications, what kinds of application methods are appropriate, etc. Instead, the response of the big box stores seems to be to skip the question entirely with combined products, e.g. "paint and primer in one".
oh, and yeah, paint and primer in one does neither job very well.
If you wanted to wait for this specific product, that's fine, but that's almost like waiting for 26% efficient solar panels instead of ~23% we already have (even though most production panels are 18% - 22%)...
And actually this is also one of those things that also helps beat Tesla Solar roof - get a white paint - THEN add bifacial solar panels. So the Tesla roof panels is actually worse for your overall cooling than regular panels now.
The white-painted object will heat less than when painted in another color, but it will heat anyway.
The white paints described in the paper and in the patent applications, which use either barium sulfate or calcium carbonate instead of the normal titanium white pigment, actually cool the painted object, even in strong solar light.
I think the catch is that if you really knew that... you'd be out making an insane amount of money as you'd be able to pick and choose winners / make them work ;)
I'm reminded of the old TV series "Connections" where lots of individual innovations are cobbled together over surprisingly long periods of time to really have an impact. Mostly... it seemed like a combo of inspiration and happenstance when someone strung them together.
https://youtu.be/XetplHcM7aQ
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2744810
In this particular case, thought, the article claims they won't be patent trolls and this paint should be cheaply available.
[1]: https://en.m.wikipedia.org/wiki/List_of_emerging_technologie...
I don't know of any compendium on the web, but if someone were looking to get started there is a field to dig into where people do this kind of work full time. It's essentially a two-sided market making process of curating useful innovations and building up a sales function to close deals.
[0] https://blog.acolyer.org/
https://www.sciencedaily.com/releases/2020/10/201021112358.h...
And they have an absurd number RSS feeds for every topic too:
https://www.sciencedaily.com/newsfeeds.htm
There is. It's called "the market". Each one of those innovative ideas gets tested by their inventors and backers against real world use-cases. Nothing validates an idea or innovation more than someone writing a check to buy it.
On their own though, right? That's not what was being asked. They wanted someway to track things that would work really well together and bring bigger benefits than things could on their own.
Yeah. When I ran a startup, you look for customers, but you also look at partnerships all the time to complement whatever you're doing. Sometimes the partnership finds you, and sometimes you find the partnership. You attend tradeshows and conferences. Sometimes your customers will point you at another company you should work with. That's all part of the market. People behind innovative technologies (inventors, and investors) are constantly looking to find ways for their tech to gain traction.
>They wanted someway to track things that would work really well together and bring bigger benefits than things could on their own.
OP is advocating for a top-down system where they can get a list of innovative technologies and just put them together like lego. It doesn't work that way. It's why a top-down command economy with a central authority doesn't work. There's a lot of trial and error (and failure) that happens at the bottom level and from the top, you just don't know what ultimately is worth expanding effort on and what is a waste of time. Any decision you make about what should go with what is going to be wrong. That's why the market is so powerful for innovation.
https://youtube.com/c/K%C3%A1rolyZsolnai
If you see this then you can reach me (in profile)
https://en.wikipedia.org/wiki/Black-body_radiation
Mirrors don't have to reflect very much, they have to reflect as a picture. That's why one-way mirrors work — people generally don't notice that the light mirrored is much less than 100%. White paint is free to reflect the photons in any direction, so that >98% is a harsher requirement on the share of incoming photons, but a laxer requirement on the photons' direction.
I'm talking about dielectric mirrors. Wikipedia suggests 99.999% or better reflectivity over a narrow range of wavelengths.
https://en.wikipedia.org/wiki/Specular_reflection
Paint reflects primarily with diffuse reflection. The rays of light are scattered in all directions:
https://en.wikipedia.org/wiki/Diffuse_reflection
What percent of the light does a mirror reflect in a specular way?
https://www.semrock.com/maxmirrors.aspx
Mirrors that are a cheaper coating on glass or metal can be in the 95% range without too much effort. If you don't care about actually forming an image with a mirror, it can be quite cheap, e.g., plain aluminum (with whatever oxide forms on its surface) or aluminized mylar film.
I'm not sure about the suggestion that people are going to paint their roofs with it. People already have the opportunity to paint their roofs with cheap white paint which would provide nearly all the benefits this would, and still choose not to do it.
> Commercially available white paints reflect between 80% and 90% of sunlight, according to lead researcher Prof Xiulin Ruan from Purdue, in West Lafayette, Indiana. "It's a big deal, because every 1% of reflectance you get translates to 10 watts per metre squared less heat from the Sun," he explained.
And yet it's hard enough even to do that.
do they get dirty fast in both humid and not humid climates? I would think in not humid, dry climates it might be more useful?
However you don’t need white to see significant benefit over a black roof, even just green helps.
Shovelling your roof with a flexible waterproof membrane can lead to gouges which defeat the impermeability. And one small leak can go unnoticed until it has seeped into the visible part of the house and rotted rafters and supporting timbers. Drainage on flat roofs get clogged and need to be cleaned or you end up with standing water.
A sloped metal roof will last for 30+ years without any maintenance. A flat roof of any type will require several maintenance operations a year and last half that unless you have a commercial tar and gravel roof which is heavy and imposes additional load bearing requirements on the structure.
One downside being that after a heavy rain, some fraction of the gravel makes its way down from the roof.
What looks great and what is not significantly affected by what are you used to see. In the place I've ground up galvanized steel roofing was common and I think it looks fine. But someone who used to dark roofs likely would tell that galvanized steel looks ugly.
That said, in the desert southwest and many places in the world, white roofs are common. I wish it were more common in the southeast...
In general I think a lot of energy savings can be realized by accommodating buildings to the prevailing climate, and using passive means of heating and cooling.
I'd never thought about ceiling height - that makes a lot of sense.
This is all known science but getting it cheap enough to be used as roofing is the trick.
In the summer, they shade the roof keeping it cooler.
In the winter, they provide an additional ventilation area that allows heat to escape without melting snow (thus mitigating risk of ice dams). Even a snow covered solar panel provides a benefit.
If it does, it’ll only be really effective until the next cleaning... and then probably just as good as plain white paint.
What is novel is that they have discovered some new method for preparing the barium sulfate pigment and mixing it with the binder, which allows very small pigment particles, possibly having a certain form, and also a very large ratio between the quantities of pigment and binder in the paint.
https://arxiv.org/abs/2011.01161
The main points are:
1. The more common white pigment titanium white is not good for cooling something exposed to sun, because it strongly absorbs ultraviolet light. (Besides generating heat, this ultraviolet absorption also causes photo-chemical reactions that degrade in time the organic paint binders.)
2. So they have chosen barium sulfate, which reflects not only visible light, but also ultraviolet and near infrared.
3. Barium sulfate not only reflects solar light, but it also emits efficiently in the far infrared, which cools the painted surface.
4. Barium sulfate was traditionally considered a worse white pigment, because it has a lower refractive index than other pigments, like titanium white.
5. The Purdue University team has overcome this disadvantage of barium sulfate by designing a manufacturing process for the pigment that not only ensures a very small average pigment particle size but also a broad distribution of the particle sizes, which results in good reflection properties over the entire solar spectrum.
The notion of painting roofs white to increase albedo is an old one (look up "Whitecap", which I was familiar with about 30 years ago). And the practical limit is of behaviour in the environment: dirt, grime, damage (hail, wind, birds, insects, ultraviolet light, etc.). It's unlikely that a "whitest white" substance will also be optimised for those characteristics.
But a durable, easily-cleaned, reflective surfacing material could prove useful.
It's all but certain that the actual applications for this material won't be as roofing. At least not for standard construction.
> “Our white is so white you can paint a chunka coal and you’d have to crack it open with a sledge hammer to prove it wasn’t white clear through.”
Of course, I'm not implying any connection to this 'whitest ever' paint, but the book is quite good.
https://en.wikipedia.org/wiki/Anti-flash_white
It was also used on interceptors like the Avro Arrow prototypes.
https://en.m.wikipedia.org/wiki/TACAMO
The Wikipedia page does say "The purpose of the colour was to reflect some of the thermal radiation from a nuclear explosion", as far as my experience goes polished metal can still get extremely hot.
A mirror would reflect light directionally, but white paint would seem to be diffuse.
Or said in another way, seeing a laser in a mirror might cause retinal damage, but on a white wall you would just see a dot. (although probably a speckly coherent dot)
I've been following news about materials which reflect in this spectrum so much, that they effectively cool their surroundings, but I understand that this paint, while probably less effective, should be much cheaper.
Honey, it’s going to be -27°C (-16.6°F) tomorrow, can you turn the reflectivity to 0% after brewing the coffee?
Mixing them as-is would ruin the effect of Vantablack. Since carbon nanotubes are black you probably would get a boring grey color with a gloss surface due to barium sulfate.
I'm curious what the effect would be if you coated Vantablack with barium sulfate. A highly reflective surface with an extreme black paint underneath.
Flip from one side to the other to help maintain temperature by absorbing or reflecting sunlight.
1: https://en.wikipedia.org/wiki/Dazzle_camouflage
I’m sure there’s some good incremental improvements here but this is over the top marketing.