Near-Infrared Persistent Paint

This Institute of Making logo has been printed with near-infrared (NIR) persistent paint. Once stimulated by sunlight, the paint becomes activated and will glow for up to 360 hours. The active ingredient is a phosphor pigment similar to fluorescent pigments, which occur naturally and are also in many products designed to be highly visible, like fluorescent jackets. However these emit light in the visible spectrum (often yellow), which can be seen with the naked eye. The term near-infrared refers to the fact that the phosphors in this sample emit light in the near infra-red wavelengths, these are invisible to the eye, but easily seen using night vision goggles (infrared radiation is heat).

This paint was created using an NIR powder mixed with a solution of oil paint, and drawn onto a high-purity alumina disk. While sunlight and solar radiation (in any weather conditions) prove to be the most effective way of activating this afterglow affect, the NIR material can also be activated by UV light and room light (it will take up to ten minutes with room light). Importantly, the afterglow can only be seen using a night vision device.

The NIR powder was created by a US-based research team at the University of Georgia, led by Zhengwei Pan, and has been considered for many different applications: as a tool for the army to offer secret night-time illumination, in solar energy, in in-vivo bio-imaging, and even as a diagnostic tool for medicine.