Transparent and anti-smudge ladder-like polysilsesquioxane coating with high wear resistance and UV aging resistance

Abstract

With the rapid development of multi-function touch panels, more requirements are raised for touch screens including anti-smudge, anti-fingerprint, and high wear resistance, hardness, and UV resistance. Herein, ladder-like poly(2-(3,4-epoxycyclohexyl)ethyltrimethoxy-co-1H,1H,2H,2H-perfluorodecyltriethoxysilsesquioxane)s (LPEFSQs) were synthesized by the sol-gel reaction of 2-(3,4-Epoxycyclohexyl)ethyltrimethoxysilane (ECTMS) with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane (PFDTES) to reduce the surface energy of the coating. The incorporation of fluorine chains resulted in an improvement of water contact angle from 77.1° to 115.5°, and oil contact angle from 35.4° to 94.7°, respectively. The omniphobic property rendered the coating excellent anti-smudge and anti-fingerprint properties while maintaining an extraordinary visible light transparency of 90.1 %. A proper PFDTES fraction of 5 % and the curing agent of I-250 are desired for the coating to simultaneously realize excellent pencil hardness of 6H, anti-smudge, and wear resistance performance. The optimized LPEFSQ coating could withstand a steel wool abrasion for 500 cycles. In addition, the developed LPEFSQ coating maintained excellent omniphobicity when subjected to ultraviolet (UV) irradiation for 200 h demonstrating excellent UV resistance. Therefore, this work provides insights into the synthesis of multifunctional coatings integrated with high transparency, wear resistance, and hardness as well as anti-smudge, and anti-fingerprint properties for touch screens.