Ultra-thin nano ink helps the plane become hundreds of kilograms lighter

The new ink weighs less than 0.5 grams per ^square meter , significantly reducing the weight of the aircraft's paint, thereby saving fuel .

The research team at Kobe University created a new structural color ink , only 100 - 200 nanometers thick and super light, New Atlas reported on January 30. New research published in the journal ACS Applied Nano Materials.

The nanospheres in methanol suspension have a different color than when applied to a surface as a monolayer. (Photo: Fujii Minoru).

Conventional paints and pigments absorb certain wavelengths of light and reflect others, but tend to degrade at the molecular level, leading to fading. Meanwhile, the structural color reflects the entire light spectrum from the parallel nanostructures, setting the appropriate distance to reject certain wavelengths. This is the effect that gives butterfly wings and peacock feathers their sparkling, gorgeous colors. Because light is not absorbed but only reflected from structures, colors do not fade. However, this effect is often highly dependent on viewing angle, resulting in a beautiful but somewhat unusual iridescent characteristic found in most industrial colorants.

In the new study, experts developed a new method to create structural colors. Instead of using parallel nanostructures, they used tiny crystalline silicon spheres . Through the phenomenon of Mie resonance , these nanospheres reflect some wavelengths much more strongly than others, which also varies with particle size. In other words, changing the particle size causes the material color to change. There is no iridescent effect because the sphere reflects light in all directions.

Notably, the color was strongest when the nanospheres had empty space around them instead of being tightly compressed. "A sparsely distributed layer of silicon nanoparticles with a thickness of 100 - 200 nanometers provides bright colors and weighs less than 0.5 grams per square meter. This makes our silicon nanoparticles one of the best coatings lightest color in the world" , said materials engineer Sugimoto Hiroshi at Kobe University.

Aviation is one of the fields that needs ultra-lightweight paint . Passenger aircraft carry about 272 - 544 kg of paint. "If we use nano sphere ink, we can reduce the weight to less than 10% of that ," Sugimoto said. Reducing weight will help the plane save fuel. Besides, because it does not fade like traditional paint, the new structural color ink also helps save on painting costs.