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'Whitest ever' paint reflects 98% of sunlight

bbc.com

211–220 of 271 posts

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

#211
post #114

Earlier quoted context omitted.

The next step is using the combination in e-ink fashion, so that you can smoothly regulate the thermal profile as needed.

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)?

You could probably use a scaled-up version of the cable mechanism used in mini-blinds.

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

#212
I have mixed barium sulfate with white paint, for making cheap reflective integrating boxes. The tricky part is maximizing the amount of powder to paint, without it getting too thick for painting. I have also used the Labsphere, integrating sphere white paint, it is also so expensive: https://www.labsphere.com/labsphere-products-solutions/mater...

On another note, the building rooftop outside my office window was painted white, within 1.5 years its gone from from blinding white to a very dark gray, I am not sure this does much good over time.

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

#213

"An infrared camera (right image) shows how a sample of the whitest white paint (the dark purple square in the middle [of the infrared image]) cools the board below ambient temperature." So... Maxwell's demon?

Well, if something can only radiate, and will absorb much less than it radiates... the only way it could stay at ambient temperature would be via contact transmission. I would expect an object painted in this whitest paint to cool below ambient temperature unless it had a heater inside it, say, or unless it was submerged in water rather than air.

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

#215
post #17

Earlier quoted context omitted.

Nice they have a White 2.0 too since last year (up to 99.6% reflective). And as with Black 3.0 banned for Colour criminals ;).

Colour criminals are defined as: 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 ow…

Finding a commercial use for polar bear fur is awesome, actually. It would ensure that polar bears never go extinct.

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

#216

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.

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.

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

#217

Earlier quoted context omitted.

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 f…

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.

So, in about 10 years we're going to have yet another source of trillions of particles of microplastic?

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

#218

Earlier quoted context omitted.

Colour criminals are defined as: 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 ow…

Finding a commercial use for polar bear fur is awesome, actually. It would ensure that polar bears never go extinct.

Like how elephants were greatly reduced in numbers to make billiard balls?

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

#220

Earlier quoted context omitted.

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.

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 homeo…

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.

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