Traditional paint gets its color from synthetic pigments, which fade over time and are not very environmentally friendly. Scientists developed an alternative is plasmonic paint, which includes color-forming nanostructures. It is more durable and economical. To cover a jet aircraft, only about 1.4 kg of new paint will be required instead of 454 kg of conventional paint. Scientists came up with the idea of a new paint by the principle of coloring the wings of ordinary butterflies.
Butterflies’ bright colors are not created by pigments, but by the reflection of light off microscopic structures on their wings. These nanoscale structures reflect and absorb ambient white light in such a way that it is perceived as bright red, blue, or green.
Scientists from the University of Central Florida reproduced this phenomenon in an experimental plasmonic dye. Along with a binder liquid, polymer resin, and isopropyl alcohol, it includes tiny, mirror-like aluminum flakes coated with even finer aluminum oxide particles. Depending on the size and distance between these nanoparticles, the flakes appear blue, purple, or yellow. Various shades of paint are obtained by mixing the primary colors of the scales in various proportions.
The aluminum used in the paint is less harmful to the environment than the synthetic pigments currently used in conventional paint. Also, while these pigments lose their ability to absorb photons over the years, resulting in a duller appearance, the nanostructured flakes give the same vibrant color endlessly.
Due to the large area-to-thickness ratio, significantly less plasma paint is required to effectively cover the surface. According to scientists, to cover, for example, a jet aircraft will require only about 1.4 kg of new paint, while the usual – 454 kg. This makes Plasmon Paint the lightest paint in the world.
Because paint reflects the entire spectrum of infrared light, it absorbs very little heat. As a result, the underlying surfaces remain 14-17 ºC cooler than if they were covered with conventional paint of the same color. This will save on air conditioners and use less electricity for cooling.
The production of plasmonic paint at this stage is only possible in the laboratory and therefore it is much more expensive than mass-produced pigmented paint. But once the technology is scaled up to commercial production, the price will become more affordable.