“Artificial Lotus Leaf” Prepared Using a 1945 Patent and a Commercial Textile

Abstract

Two polyester textiles, conventional polyester and microfiber polyester fabrics, were hydrophobized using a simple, patented water-repellent silicone coating procedure. Water contact angles on these two surfaces are θ_A/θ_R = 151°/140° and θ_A/θ_R = 170°/165°, respectively. A smooth surface of this of this coating exhibits θ_A/θ_R = 110°/100°. The binary length scale topography (∼2 μm/∼50 μm) of the microfiber polyester is responsible for relieving receding contact line pinning and promoting water repellency that is superior to that of the lotus leaf. The recent literature on superhydrophobic surfaces is criticized for neglecting literature of the 1940s.