Superhydrophobic Coating for Antifouling of Chinese Paintings

In the past 10 years, many studies on superhydrophobic (SH) papers have been reported. However, these works are rarely carried out on Chinese paintings. Compared with pure paper, the complexity of Chinese black ink and pigment, caused by including animal glue and fixatives allowing the nanoparticles to disperse in water, negatively affects the formation of SH coatings. In this work, we report the fabrication of SH coatings using fluorine silicon sol containing an epoxy group on Chinese paintings. Briefly, SiO₂ nanoparticles were mixed with KH560 and FAS-17 and formed fluorine silicon sol. Then the sol was coated on the Chinese paintings. After drying, the SH coating was created. It can protect Chinese paintings and prevent them from being fouled by various liquids. Six types of beverages and ink can be repelled by the as-prepared SH coatings. Moreover, Chinese black ink can also be washed away from the SH coatings using water, without leaving any traces of ink behind. The SH coatings did not affect the appearance and internal structure of the Chinese paintings. Furthermore, due to covalent link, the SH coatings have good mechanical properties with regard to bending tests (120 times), finger pressing tests, and friction tests. The SH coatings also show an excellent high temperature resistance. This study has important applications for antifouling of Chinese paintings or oil paintings from dirty water.