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'Whitest ever' paint reflects 98% of sunlight

bbc.com

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Re: 'Whitest ever' paint reflects 98% of sunlight

#221

Post by dredmorbius »

nvahalik wrote: post #27

Yeah it’s white but does dust and debris still stick to it? If it does, it’ll only be really effective until the next cleaning... and then probably just as good as plain white paint.

Right.

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.

Re: 'Whitest ever' paint reflects 98% of sunlight

#224

Post by dcanelhas »

Duralias wrote: post #134
TorKlingberg wrote: post #118

Earlier quoted context omitted.

This makes me wonder, does "anti-flash white" reflect more than polished mirror-like metal?

Maybe not more, but different wavelengths. 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.

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.

Re: 'Whitest ever' paint reflects 98% of sunlight

#225

Post by dcanelhas »

TorKlingberg wrote: post #118
a4isms wrote: post #46

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. https://en.wikipedia.org/wiki/Anti-flash_white It was also used on interceptors like the Avro Arrow prototypes.

This makes me wonder, does "anti-flash white" reflect more than polished mirror-like metal?

https://www.researchgate.net/figure/Spectral-reflectivity-of... apparently most polished metals tend to absorb quite a lot of light in higher frequencies (shorter wavelengths).

Re: 'Whitest ever' paint reflects 98% of sunlight

#226

Post by bsanr2 »

cyberlab wrote: post #4

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…

The Two Minute Papers YouTube channel covers new research related to (visual) simulation and AI. It's like a weekly mini-Siggraph.

https://youtube.com/c/K%C3%A1rolyZsolnai

Re: 'Whitest ever' paint reflects 98% of sunlight

#228

Post by macleginn »

samatman wrote: post #183
quickthrowman wrote: post #64

Earlier quoted context omitted.

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 tec…

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…

As one of my uni professors said, if the Persians had not annihilated Miletus, the humanity would've walked on the Moon much sooner.

Re: 'Whitest ever' paint reflects 98% of sunlight

#230

Post by zimpenfish »

irrational wrote: post #222

So, now we have the blackest black paint ( https://mymodernmet.com/stuart-semple-black-paint/ ) and the world's whitest white paint. There must be something cool we could do with the two of these.

> blackest black

Musou Black has a slight edge over Black 3.0.

https://www.ko-pro.black/2020/05/14/black-3-0-vs-musou-black...

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