Heterogeneously-wetting glass with enhanced anti-fingerprint properties

Abstract

The rapid development of user interface products (such as touch-operated smartphones, panels, and computers) has tremendously changed how we interact with technology. Inevitably, undesirable fingerprint oil contamination is often left on touchscreen glass, significantly impairing the users' visual experience. To date, attempts based on oil-repellent or oleophilic coatings have been utilized to prevent the deposition of fingerprints on glass. However, these methods exhibited limited performance, particularly under real-world conditions. Inspired by the heterogeneous wettability of Stenocara beetles, we designed a novel heterogeneous glass surface, made up of nanopillars consisting of oleophilic top surfaces with oleophobic sidewalls and bases. This configuration combines the anti-fingerprint properties of both oleophobicity and oleophilicity. The beetle-like heterogeneous structures with remarkable wettability contrast enable excellent optical and wetting properties, including high transparency, low haze, hydrophobicity, and oleophobicity. The synergistic integration of oleophobic and oleophilic characteristics contributes to the non-uniform distribution of adhesion force, leading to a 74.6 % increase in fingerprint resistance and a 59.2 % increase in the ease of fingerprint removal over conventional oleophobic glass. The heterogeneous glass also maintained stable anti-fingerprint properties after ten standard cycles of finger touch and wiping, and even up to 1000 cycles of continuous wiping, illustrating good mechanical robustness. Thus, our findings provide a new route for the future design of anti-fingerprint glass.