Super Oil-Repellent Surfaces

摘要

Surfaces that repel both water and liquid oils completely are very useful in daily life and in industry. Although surfaces with outstanding water-repellent properties have been developed and intensively studied recently, surfaces with excellent oil-repellent properties, however, have not yet been reported in spite of their crucial importance. Wettability of a solid surface with a liquid is enhanced by the surface roughness, in particular by the presence of fractal structures. When the contact angle between a liquid and a flat solid surface is larger than 90°, the surface repels the liquid completely if the surface rough enough.