YInMn, the First New Blue Pigment in Two Centuries | Hacker News Reader

YInMn, the First New Blue Pigment in Two Centuries

hyperallergic.com

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Previous discussions:

https://news.ycombinator.com/item?id=25807199

https://news.ycombinator.com/item?id=25886601

Two articles about the discovery:

https://www.npr.org/2016/07/16/485696248/a-chemist-accidenta...

https://www.bloomberg.com/features/2018-quest-for-billion-do...

I haven't found it in previous discussions, could anyone explain to me why is this significant? I have clue about painting artistically but when you want to get a wall paint, or some plastic, you can basically get any color you want. So why is this important?

I'm guessing that maybe most colors I see are a mixture of CMYK or something alike, but if my eye can't tell the difference, does making something only reflect a single frequency instead, matter for somebody looking at an object?

Essentially, while you might be able to get any colour you want, others (mainly artists, it seems) have not been able to get any colour they want. This one has better properties than previously available pigments. Read the article.

So in a very, very simplified way, you can imagine the color space like a triangle with Red, Green and Blue at the corners.

By mixing, you can reach any color within the triangle — but you can‘t leave it, as then you‘d have to start from an even "bluer" blue.

This is basically what the new pigment enables, and not just that: This shade seems to be way more color stable over time. All colors fade eventually (especially with UV irradiation), so if you want to preserve the original color in a painting for example, this matters.

OK, but we only have 3 types of cones, so unless you make a pigment hitting the exact frequency of our blue cones, there is not really any difference in perception, is that correct?

I am neither a painter nor a chemist, but this is significant to me as a general science person in a meta(l) kind of way.

Most useful compounds, even alloys, of only metallic elements, tend to be composed of MAINLY two metals. (usually they are 2 main ones plus many lesser metals) This one is composed of THREE and isnt even a metal.

There doesn't seem to be much of a perceptual difference from Cobalt Blue. [1]

The significance is mainly due to better durability [2]:

> the increased UV absorbance and stability in outdoor weathering and heat buildup tests demonstrate that YInMn blue is superior to Cobalt Blue

[1] https://www.sciencedirect.com/science/article/abs/pii/S01437...

[2] https://chemistry.oregonstate.edu/content/story-yinmn-blue

The article links to a paint company that is using the pigment, cool video of them adding it to paint. (sorry for FB video)

https://www.facebook.com/watch/?v=405127556741940

Here is a link to a more recent article by Golden Paints with the video embedded.

https://justpaint.org/custom-special-edition-yinmn-blue-acry...

Been waiting on this to be available ever since it was first announced. Finally got an email last year from a paint supplier (Gamblin), and a single 37ml tube is $75... with a limit of 2! I really hope at some point that these 'rare earth' ingredients come down and it can be more readily available / cheaper. I'd seriously paint my roof and my whole house with it to keep it cooler in the summer.

It's likely expensive because of the synthesis and quality control not because of the raw ingredients (not that they're necessarily cheap either).

Indium is a bit more expensive than silver at the moment, the other two are much cheaper.

So yes, synthesis, quality control, probable patent encumbrance, and high demand, more than raw ingredient price: but it'll never be particularly cheap.

But how many grams of pigment in a can of paint?

Possibly a stupid question, but why would painting your roof blue help keep it any cooler than painting it white for example, which reflects more light?

Edit: Ok it turns out there's 2 parts to a cooling roof, how reflective it is, and how good it is at emitting infrared radiation (emissivity). Reflectivity of visible and UV light prevents more energy from being absorbed, but doesn't necessarily mean the material cools down well once hot. A high emissivity means the material can cool down quickly through radiation.

I guess YInMn blue has a high emissivity.

https://en.wikipedia.org/wiki/Reflective_surfaces_(climate_e...

I cannot think of any reason why blue would ever have a lower emissivity than actual white.

Rare earths are not going to come down in price, in my opinion. They're used in too many places and have too few sources. The US has a rare earth strategy document that makes clear just how insecure supplies of these elements is.

Thanks, I was not familiar with the concept of emissivity.

I cannot think of any reason why a material's absorption/emission through the visible spectrum would determine its absorption/emission through the infra-red spectrum.

That is why I said "actual white".

So "actual white" has little to do with the color that we see.

Is it also white to the x-ray spectrum and the radio wave spectrum? If so, I am pretty sure that this doesn't actually exist.

Right, it doesn't actually exist. It is a technical definition that by definition absorbs no light, it isn't a practically realizable thing.

Yes, you're describing a white body, the opposite of an ideal black body. It does not exist, of course. But we can try to approximate one with materials, at least for IR through UV. Now, if we do have a pigment that can reflect X-rays... I'd definitely want my roof painted with that.

> x-ray

Easy to ignore since it won't be hit by any.

> radio

I dunno, how hard is it to get materials that reflect radio waves?

It's probably reasonable to talk about materials that reflect almost all the light in frequency bands of non-negligible power as effectively being actual white.

There is a glut in supply of some rare earths as they're byproducts of refining the more valuable ones.

You are absolutely correct, but the ratios of their availability, because they are a byproduct, all go up by the same proportion. It's hard to avoid excesses of the less useful ones with shortages of the more useful ones.

More useful ones being things like neodymium and erbium and cerium.

Once one of them is not being produced in sufficient quantity due to being a byproduct, then it gets really expensive. That's for sure.

(edited for clarity)

Your edit is an excellent point, thanks for the addition. If it is white in the visible but black in the infrared that could help with cooling sure.

Personally I'd probably focus on windows and solar insolation from that first, especially since the roof is insulated, but that makes more sense.

> I'd seriously paint my roof and my whole house with it to keep it cooler in the summer.

It'd likely be more effective to do some combination of insulation, radiant barriers, and thermal breaks.

> ... the First New Blue Pigment in Two Centuries

What about Phthalocyanine Blue, a very widely used highly regarded synthetic blue first industrially produced in 1935?

This is what Wikipedia says about Phthalocyanine Blue: "It is highly valued for its superior properties such as light fastness, tinting strength, covering power and resistance to the effects of alkalis and acids."

Two shades of it are available in the Golden artist paints.

Based on the facebook video, it's not as strongly tinting as either ultramarine or cobalt blue, and it's close enough to cobalt blue in hue that I don't see what the point is unless it's less expensive than what is traditionally one of the most expensive pigments on a palette.

Aside from the novelty of the newness, it won't matter for artists unless it's a less expensive alternative, because visually, there's nothing there that you can't get cheaper.

> Based on the facebook video, it's not as strongly tinting as either ultramarine or cobalt blue, and it's close enough to cobalt blue in hue that I don't see what the point is unless it's less expensive than what is traditionally one of the most expensive pigments on a palette.

According to the OP:

> Blue pigments, which date back 6,000 years, have been traditionally toxic and prone to fading. That’s no longer the case with YInMn, which reflects heat and absorbs UV radiation, making it cooler and more durable than pigments like cobalt blue.

> “The fact that this pigment was synthesized at such high temperatures signaled that this new compound was extremely stable, a property long sought in a blue pigment,” Subramanian said in a study about the compound.

As long as stuff doesn't fade for 50 years, are artists bothered? After you're dead, nobody is going to come and complain at you for using a non-durable choice of pigment.

Needless to say,yes artists are indeed bothered about the properties of their paint.

> As long as stuff doesn't fade for 50 years, are artists bothered? After you're dead, nobody is going to come and complain at you for using a non-durable choice of pigment.

I'm sure many artists aren't creating for wholly hedonistic reasons, and instead want to create things that will endure.

A lot of successful artists are very conscious of perservation and archival concerns. It's not just that basic professional level art materials are very deliberately marketed as archival quality: it's a fashion these days to paint on metal surfaces, either sheets of copper, or aluminum composites like Dibond, used by sign painters. Dibond is two sheets of aluminum sandwiching a 2mm layer of polyethylene.

What these surfaces have in common is that they're dimensionally stable: they don't change in size depending on temperature or humidity, and they're chemically impervious to the ground layer. Oil paints can degrade linen canvas over time as the oil seeps into the fibers and oxidizes.

After your dead, no one comes back for you. Instead, your most visible legacy in this world slowly falls apart, changing color, getting brittle, and looking decrepit before it falls apart. Artists aren't invulnerable to vanity.

Rennaissance paintings of the Virgin Mary, for which ultramarine blue was the traditional expensive pigment, are as vivid today as when they were painted five centuries ago. Mineral pigments like ultramarine (i.e., finely ground lapis lazuli) are essentially perfectly lightfast. Cobalt blue is a metal rather than a silicate but still considered gold standard lightfast where artists are concerned: Chinese pottery has used it for millenia and shown no tendency to change hue. Cobalt blue is toxic but ultramarine isn't.

It's possible that YinMn is similarly lightfast, but the historical blues remain cheaper and more than lightfast enough for virtually any artist concerned with longevity.

Awesome, does that mean OSU can ditch prison orange as its school color now?

Ok, waiting for a good red though.

I'd confidently say that these days many people haven't much of a clue about the full range of the shades of blues that their eyes can actually see and if they did then they'd be rather surprised!

Unless you're a gardener or a flower grower who specializes in blue flowers or a lepidopterist specializing in blue butterflies you'll have spent most of your life looking at a very limited range of blues. You many think you've seen many shades of blue and you probably have except that most of the blues you've seen have come from a very limited range of dyes and pigments—in essence, your normal viewing experience of blues comes from this rather limited subset. These you'll encounter as pure dyes or pigments or various mixtures thereof. To provide light shades of blue white is added and to make the blue hue appear 'richer' small amounts of other colors, typically red, are added (it's a form of cheating/fooling the eye so to speak).

Right: that seems like many shades of blue available—and it is—but each of this limited range of dyes and pigments has its own intrinsic characteristic spectral response, thus each blue has an underlying 'characteristic blue' appearance common (and often recognizable) to all those shades and intensities. The trouble is that our eyes are remarkably discerning and they can see a much larger range of blues that exist outside our present commonly available range of blues.

Superficially, there seems to be a sufficiently large range of blue dyes and pigments available for our needs; for example, to name the more common, Azo dyes (diazo blue), indigo (jeans blue), Prussian blue, lapis lazuli (ultramarine), cobalt blue, copper-based blues–Egyptian blue, azurite, etc. However, the range of available blues is quite limited when one takes into consideration the physical and chemical properties of each dye and pigment, as sufficient numbers are either unstable and or are not suited to the industrial processes (printing, dying plastics, clothes dying, etc.), or they're rare and hellishly expensive (lapis lazuli for instance).

Another reason many haven't experienced the full spectrum of blues the eye is capable of perceiving is that blues aren't all that common in nature. It's worth taking a few minutes to watch this YouTube video titled "Why Is Blue So Rare In Nature?" https://www.youtube.com/watch?v=3g246c6Bv58. (Given the fact that blue is so rare in nature, what surprises me is the unanswered question of why the human eye has nevertheless thus evolved to be so discerning in the blue region—anyone any ideas?)

This brings me to the next point, which is to mention how a curious person can easily check his or her eyeballs out on a range of extended blues that are outside those that we normally encounter (à la those listed above). Several decades ago, I attended an electronics engineering conference where much of the subject matter was on the colorimetry of color television and I was thinking about the fact that the color gamut of television was limited by the comparatively poor performance of the blue phosphor (amongst other things). Not being in my home city, between conference times I found myself occupied wandering through the nearby park where to my surprise I stumbled across a conservatory full of brilliantly colored cineraria flowers (Pericallis × hybrida), many of which where dazzling shades of blue—blues that were way outside the color gamut range of normal color film, color TV, printing and dyed objects.

As colorimetry has occupied part of my career for years, I'm very perceptive of color and coming across a huge variety of brilliantly colored cineraria was quite an eye-opener [duh]. Cineraria come in all sorts of dazzling colors but those that I'm principally interested in are the blue ones. There are two interesting properties of many (but not all) cineraria flowers and they are that the color of their petals is most intense (saturated) at their outermost extent and that this color progressively and completely fades to pure white near the center of the flower; and second, there is a phenomenal range of hues and levels of saturation within each color group (with the blues being the most spectacular). (If you're unfamiliar with cineraria, do an image search on "blue" + "cineraria".)

The important aspect of seeing cineraria in public gardens' conservatories is that one can see, compare, and experience this vast variety of colors that would be very rare to experience elsewhere. Whenever I'm in a city for the first time, I'll often check to see if there's a cineraria conservatory there. Of the best two conservatories I've come across one is in Longwood Gardens, Kennett Square, Chester County, PA, https://plantexplorer.longwoodgardens.org/weboi/oecgi2.exe/I...; and the other in Fitzroy Gardens, Melbourne, Australia, https://vimeo.com/288066051, however I'm sure there are many more elsewhere. As I've stressed, the blue colors you'll see in the cineraria images in these links is only a rough guide to what you'll actually see in real life—the artificial colors just can't match the real thing! (If you intend to visit a cineraria conservatory then time it to be when the plants are in full bloom and do so on a bright day when natural daylight is at its peak.)

My commentary about cineraria isn't to put a scientific measure on what I've said but only to demonstrate that "A Good Blue Is Hard to Find" and it's always been so throughout history—and that you can demonstrate the fact for yourself just by looking at these flowers. Incidentally, the quoted text in the last sentence is the title of a book review in Scientific American by Peter G. Brown of Bright Earth: Art and the Invention of Color by Philip Ball (SciAm ISSN 0036-8733, Vol. 286, Nº 3, 2002, pp 98-100). There's more about the book below.

Finally, this brings me to the point about YInMn blue. I recall the announcement of its discovery in 2009 (as any new blue is a big deal). There is no doubt that it's sorely needed and that it will be a most welcome addition to the range of available blues (As yet, I've not seen it in the flesh but I'm eagerly awaiting the experience). There's no doubt that it will extent the range of blue hues and add considerable vibrancy to the color (soon expect to see important extensions (new numbers) to the blue range of Pantone colors). ;-)

While YInMn blue will go along way to improving the 'reproducible' blue spectrum, it nevertheless won't solve the blue problem completely. For starters, it's only useful for printed material and coloring physical objects, it doesn't help with the reproduction of electronic colors, TVs, displays etc. Also, there's still the need to give better vibrancy to the existing range of blues (ultimately, we still need to add vibrancy to the older [spectral] range blue dyes and pigments so as to balance them with the brighter, more vibrant YInMn blue).

If you're interested in the subject of color then the book 'Bright Earth: Art and the Invention of Color' by Philip Ball is an excellent place to start. The mentioned SciAm review isn't available on line but these two ought to suffice:

http://www.librarything.com/work/206920/reviews/68183903

https://www.theguardian.com/education/2002/jan/26/highereduc...

Note: I'm only familiar with the 2002 edition so I am unable to say whether Philip Ball has included the 2009 info about YInMn in his later 2010 and 2012 editions.

Since posting above comment I've discovered that 'Bright Earth: Art and the Invention of Color' was also mentioned by getpost in a post to the same but earlier story at:

https://news.ycombinator.com/item?id=25807199

Posts to it are now closed so there's no way of cross-referencing them.

Why is this article on the front page of HN? As of late, HN is becoming more popular science-ish instead of hackish.

Science is hacking .

Right, but in its notes concerning Hacker News Guidelines, https://news.ycombinator.com/newsguidelines.html, HN makes the point about the website:

"Hacker News Guidelines/What to Submit

On-Topic: Anything that good hackers would find interesting. That includes more than hacking and startups. If you had to reduce it to a sentence, the answer might be: anything that gratifies one's intellectual curiosity."

That's pretty broad, as it says it "includes more than hacking...".

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