Japan Invented The Structural Coloring Method To Show Colors Without Dyes.

Have you ever wondered how the beautiful colors of butterfly wings come into being? Where does the metallic luster on the beetle's back come from?

The secret is that light is produced by the reflection of tiny gaps on their body surface, which is called "structural coloring".

Following the footsteps of nature, researchers at Kyoto University developed a way to produce full color and fade free images without using ink.

To produce this effect, Vosa Sylvania, a professor of materials science at the University's comprehensive Cell Materials Science Institute, and his colleagues made tiny holes in plastic films used in bottles and put them in an acid solution.

The light interruption caused by the uneven flat surface causes the coloring of the structure, which is very similar to the phenomena in nature.

The team said that the study may lead to the development of low-cost printing technology, because no pigment is needed, and the materials and reagents involved are cheaper than traditional methods based on pigments.

Itou Masahiro, a researcher at the University's comprehensive institute of cell materials science, points out that it can be applied to banknote anti-counterfeiting technology.

Details of the research project were published in the online edition of the June 20th British science journal Nature.

Researchers have shown that this method can produce color in the whole visible spectrum, and the shape and size of the image can be adjusted.