Scientists Made A Car Paint So Black It Barely Reflects Light

Car Paint Darker Than Almost Anything on Earth Just Cleared a Key Hurdle

There’s black, and then there’s black, the kind that seems to swallow light whole, turning a car into something that looks less like a vehicle and more like a hole cut into reality. That visual effect has long been the holy grail of luxury automotive design, but making it work with paint that can survive water exposure and humidity, let alone the full gauntlet of real-world road tests, has proven maddeningly difficult. Now, researchers at Nippon Paint in China say they’ve cracked a promising early piece of that puzzle.

A team of scientists there has developed an ultra-black automotive coating that absorbs more than 99.9% of visible light, according to a study in the journal Matter & Light. It uses a carefully engineered combination of two forms of carbon: ordinary carbon black, the pigment that has colored car paint for decades, and carbon nanotubes, tiny cylindrical structures that are exceptionally good at trapping light. Together, they form a coating that is extraordinarily dark and shows strong adhesion results after humidity and water-resistance testing, a meaningful early step in the longer validation process the industry requires.

Standard Black Paint Has a Ceiling It Can’t Break Through

Standard automotive black paint relies on carbon black, a fine, dark powder that absorbs a large portion of light. It works reasonably well, but there’s a ceiling. Those extremely small particles have a stubborn tendency to clump during manufacturing. Those clumps scatter light rather than absorbing it, washing out the depth of color and leaving conventional black coatings absorbing around 99.8% of light at best.

That gap between 99.8% and 99.9% might sound trivial, but in high-end automotive color, it translates to a visible difference, the kind of deep, almost disorienting blackness that luxury and sports car buyers pay a premium for. Car companies have been chasing this effect for years. In 2019, BMW debuted a concept vehicle coated in Vantablack, which absorbs up to 99.96% of light but is far too fragile and process-intensive for production use.

Carbon Nanotubes Give Ultra-Black Automotive Paint Its Record-Breaking Darkness

Carbon nanotubes, essentially sheets of carbon atoms rolled into microscopic tubes, are exceptional light absorbers. The problem is that they are notoriously difficult to keep evenly distributed in a liquid coating mixture; they tend to clump, separate, and settle over time. To solve this, the team used a high-energy milling process to grind the carbon black and carbon nanotubes together in water along with dispersing agents. An accelerated stability test put the mixture through centrifuge forces more than 2,000 times the pull of gravity over seven hours, with only minimal separation, a strong indicator of shelf-stable industrial viability.

Because carbon black and carbon nanotubes share a chemical property that causes them to attract each other, the carbon black particles lined up along the nanotubes like beads strung on a wire rather than mixing randomly. Researchers describe this as a “connecting-the-dots” structure.

This arrangement creates a tiny, irregular surface texture on the coating, a landscape of microscopic peaks and valleys. When light hits this surface, it bounces around inside those valleys rather than reflecting back out, getting absorbed repeatedly, similar to soundproofing foam in a studio. Researchers call this “structural absorption,” and it’s the key mechanism that pushes the coating past the limits of conventional carbon black paint.

Ultra-Black Car Paint Scores Far Higher Than Conventional Black on Key Color Metrics

To measure how black a coating actually is, the automotive industry uses two numerical scales, “jetness” and “blackness,” where higher numbers mean a darker, more visually intense color. Standard carbon black coatings have essentially maxed out what’s achievable with that approach alone. The new coating posted meaningfully higher scores on both scales than the conventional formula tested alongside it, a level the paper describes as very difficult to achieve with standard water-based approaches.

Average reflectance across the visible light spectrum came in at approximately 0.08%. For context, Vantablack reflects about 0.04% of light, while common carbon-based coating materials typically reflect 1.5% to 4%. The new coating sits between those extremes, dramatically darker than conventional paint and applied using standard automotive spray equipment.

Automotive coatings must pass a battery of tests before manufacturers will consider them. Two sets of test panels were separately exposed to high temperature and humidity for 14 days and submerged in a water bath for 10 days. After each trial, a standard tape test on a grid of surface cuts checked for adhesion. Both sets passed with no visible defects and no detachment. Broader real-world testing still lies ahead before any production use could be considered.

For luxury and performance car buyers, ultra-black paint signals a particular kind of visual authority. Getting this level of darkness into a sprayable, water-based formula that passes early adhesion testing is a meaningful step forward, even if the road to a production car still has distance left to travel.

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