Color plays a very important role in our lives. Artists and designers know that it can influence physical and emotional state of people, so they put special emphasis on color while creating works of art. When it comes to working with metals, laser coloring of surfaces significantly outperforms other methods out there. The laser technique provides a wide palette of colors and boosts the control of color parameters, unlocking many new opportunities for creativity. Now one can use lasers as a tool or a brush, with metal being the canvas.

The developers of the new technology from ITMO University found a way to paint on the surface of silver using a laser as the only tool. The technology is based on ​​creating nanoparticles of various sizes on the surface of a precious metal. The color appears due to the plasmon resonance effect and depends on the size and distribution of nanoparticles. This technology makes it possible to quickly and accurately transfer any image on a silver surface.

The operating principle of the laser coloring technology
The operating principle of the laser coloring technology

“First, following the example of the technology used in our startup ColorIT, we came up with a two-step method of coloring precious metals. We applied a metal film on the product, which was then subject to oxidation due to laser exposure. However, we wanted to avoid additional steps, equipment and materials. As a result, having analyzed the relevant literature and conducted thorough research on the topic, we concluded that the phenomenon of plasmon resonance is ideal for creating jewelry and even works of art made from precious metals. We’ve discussed our findings in a recent article on the laser decoration of metal surfaces,” commented Galina Odintsova, a researched at ITMO University and the head of the ColorIT startup. 

The scope of the new technology is wider than the jewelry industry. It can also be used in the fields related to the creation of unique surface properties of metals. In addition, the resulting silver nanoparticles can be used to obtain color images on polymers.

Galina Odintsova
Galina Odintsova

Now scientists are working on expanding the palette of the resulting colors, as well as on increasing the image durability. In the near future, they also plan to establish the color palettes to be used on gold and copper surfaces.

Reference: High-resolution large-scale plasmonic laser color printing for jewelry applications. G. Odintsova et al. Optics Express. February 1, 2019.