Facile fabricated transparent anti-smudge coating with high hardness and excellent flexibility from MTQ and branched silicone resins

The demand for high-transparent functional coatings with glass-like hardness, polymer-like flexibility, and anti-smudge properties has increased significantly, especially for foldable touchscreens. However, it is challenging to achieve all the required properties in a coating because the realization of these properties may conflict with each other. In this study, we present a facile method for preparing a special organic-inorganic hybrid coating by utilizing epoxy MTQ silicone resins and amine-terminated hyperbranched polysiloxane (HPSi). The chemical structure of the MTQ resin was fine-tuned to obtain the optimal M/T/Q ratio, and a novel HPSi with rich crosslinking sites and excellent flexibility was prepared as the curing agent. The resulting hybrid network imparted the coating with exceptional hardness (pencil hardness, 7–9H) and excellent flexibility (<2 mm bend diameter). In addition, by modifying the MTQ resin with fluorosilane, the surface energy of the coating was reduced to 14.8 ± 0.4 mJ/m2 and its anti-smudge and self-cleaning properties were improved without sacrificing the transparency of the coating (99.4 % at 550 nm). Notablely, even after 1000 cycles of steel wool abrasion, these coatings still maintain their outstanding performance. This study provides a promising strategy for the development of hard, flexible, and anti-smudge coatings suitable for foldable displays and other related fields.