2D Prior Spreading Inspired from Chinese Xuan Papers

Liquid spreading is fundamental to many applications in interfacial materials. However, anisotropic spreading inside superlyophilic fabrics, playing an important role in clothing materials, ink printing, medical masks, and paper manufacturing industry, is rarely studied. Here, a special wetting phenomenon is introduced on Chinese Xuan papers, a kind of handmade papers dating from thousands of years ago in China, mainly for painting and calligraphy with Chinese brushes. Different from other papers or porous materials, liquid, such as ink, prefers to spread along the 2D direction, meaning that liquid can spread out rapidly while it seldom permeates through the papers, avoiding blotting of the underlying sheet. The antipermeation test shows that 150 µL of water is added to Xuan papers without permeation, which is attributed to the multilayered spreading, resulting from the layered anisotropic micro/nanofibrous structures. Inspired from this, similarly structured fabrics with liquid 2D prior spreading and antipermeation abilities are electrospun. About 175 µL of water is able to spread completely without permeation. These findings demonstrate a new wetting concept for manufacturing antipermeation materials with controlled ultrafast 2D spreading properties.