Visually invisible multimode anti-counterfeiting based on highly transparent superamphiphobic/superhydrophilic pattern

Anti-counterfeiting technology can identify the authenticity of products, which plays an increasingly important role in combating piracy and protecting intellectual property. For optical products or devices, such as optical lens, glasses, screens and photovoltaic components, optical transparency and visual invisibility are highly necessary for the applied anti-counterfeiting technology. Herein, a visually invisible multimode anti-counterfeiting material was designed by constructing highly transparent superamphiphobic/superhydrophilic wetting pattern. The anti-counterfeiting pattern was invisible under normal conditions due to the high transparency of the wetting pattern, which enables the camouflage advantages of the anti-counterfeiting pattern. While under the treatment of fog by steam or halitus, the pattern can become visible in seconds due to the transmittance difference between the superamphiphobic and superhydrophilic area, owing to the distinct light scattering behavior between liquid droplets on the superamphiphobic area and liquid film on the superhydrophilic area. The excellent lyophobicity of the superamphiphobic area and its distinct surface energy gap to the superhydrophilic areas endow excellent pattern stability and robust in practical applications. With additional invisible fluorescent molecules on the superhydrophilic area, the multimode anti-counterfeiting pattern also becomes visible under ultraviolet light, which can further improve the security of the anti-counterfeiting pattern. Owing to the visual camouflage, simple writing/reading procedure and function expansibility, we believe that this transparent wetting pattern based visually invisible multimode anti-counterfeiting material will be attractive for the areas of optical surfaces and devices.