If a color can hold a world record, Surrey NanoSystems says its super-black coating known as Vantablack does. The coating holds an "independently verified world record as the darkest man-made substance," according to the company website. But what exactly is Vantablack and is it really the blackest black?
Technically, Vantablack a pigment coating developed in 2014 by Surrey NanoSystems. The name is an acronym for Vertically Aligned Nano Tube Array Black. The company says Vantablack absorbs 99.965 percent of light, which made it the blackest of all blacks at the time.
What Is Vantablack?
Vantablack was originally designed for use in space travel and optics as an application on sensitive materials to help improve the visibility of distant objects being studied. For example, coating a telescope in Vantablack absorbs glare, making it easier for users to see distant stars and planets.
Surrey NanoSytems' first Vantablack process used chemical reactions to "grow" millions of microscopic filaments of carbon nanotubes (CNTs) to the surface of the object being coated. The CNTs stood on end and were packed tightly against each other.
The CNTs absorb nearly all the light that reach the object, making it appear like a black void. Normal black objects or pigments absorb light — that's why a black car gets hotter on a sunny day than a white car — but they still reflect enough light to be seen. The goal of Vantablack is to absorb as much light as possible, which, when successful, strips the object of visible depth and texture, leaving only a silhouette.
Newer versions of Vantablack use different arrangements of the carbon nanotubes, enabling more traditional application techniques to achieve a similar effect. These versions can be sprayed on — using robots — and don't have to be grown in a CVD reactor. That makes Vantablack more versatile — and explains how it ended up on a BMW X6 SUV as well as on the high-tech space equipment.
Vantablack and BMW
Numerous car companies approached Surrey NanoSystems about coating a car in Vantablack VBX2 paint finish, but it wasn't until BMW came calling that the company finally agreed. "We turned down numerous requests from various automobile manufacturers in the past," Ben Jensen, founder and chief technical officer of Surrey NanoSystems, said in a press statement. "It took the BMW X6 and its unique, expressive design for us to entertain the idea."
The VBX2 paint makes the BMW X6 appear 2D, though angles still provide slight reflection. So what was BMW's goal, besides drawing attention to the X6 SUV? Once coated in Vantablack, the company's design team was able to study the vehicle in an entirely new way, focusing on proportions and silhouettes, without the numerous distractions hidden by coating.
Though the BMW X6 is a one-off just for show, it can teach designers a lot about the coating, its capabilities and its limitations. For example, modern safety systems that rely on complex sensor networks — specifically LiDAR systems that pick up reflected light — can still see the X6. One such system is the emergency braking system that automatically slows or stops your car if you get too close to the car in front of you. LiDAR company Ouster tested its lasers on the BMW X6 and the car was still perceived by the braking system. In other words, even though Vantablack makes the car nearly "invisible," advanced technology seems to still be able to detect it.
Can You Buy Vantablack?
Vantablack is still hard to manufacture, and it's expensive, so it's not available for sale commercially. But Surrey NanoSystems does provide samples to universities, museums and research institutions to display.
And because it requires such a special application, the company has licensed its Vantablack S-VIS use only to artist Anish Kapoor of Kapoor Studios UK. It's not like just anyone could just call up and acquire a couple gallons of the stuff anyway, but the move ruffled a lot of feathers for going against the spirit of the art community.
But other artists have proven you don't need a high-tech lab or a ton of money to get a similar effect on a small scale. Artist Stuart Semple created two matte black acrylic paints, Black 2.0 and Black 3.0, which are pretty darn black. Though they are not the blackest blacks in existence, Semple's site notes that's the trade-off for being affordable, accessible, easy to use and available online. (See Now That's Interesting below for more details.)
In fall of 2019, engineers at MIT revealed a new, even darker black coating, which is capable of absorbing 99.995 percent of visible light. MIT's coating is also made of vertically aligned carbon nanotubes (CNTs) and was developed for optical and space science applications.
Still, others in the art community and elsewhere are invested in finding the absolute limit of the blackest possible black, so it's possible we may one day be able to capture those remaining hundredths of a percent of visible light.