Surfaces and articles resistant to impacting liquids

摘要

Articles resistant to wetting by impinging droplets of liquid are presented, as well as a method for resisting wetting of an article by impinging droplets of liquid. For example, an article (300) comprises a surface portion (320) oriented to intercept droplets (310) of a liquid impinging upon the article (300). This surface portion (320) comprises a plurality of surface features (330), wherein the plurality of surface features (330) has a median size, a, a median depth, h, and a median spacing, b. The parameters a, b, and h are selected to generate, in response to a droplet of the liquid impinging upon the surface portion (320) at a relative velocity v, a back pressure that is greater than a Bernoulli pressure generated by the drop upon impact on the surface portion (320). The method comprises providing a surface portion (320) oriented to intercept incoming droplets (310) of a liquid, the surface portion (320) comprising a plurality of features (330) so disposed on the surface to generate, in response to a drop of liquid impinging upon the surface portion (320) at a relative velocity of at least 5 m/s, a back pressure that is greater than a Bernoulli pressure generated by the drop upon impact on the surface portion (320); and exposing the surface portion (320) to droplets (310) of liquid moving at a velocity of at least about 5 m/s relative to the surface portion (320) so that the droplets (310) impinge upon the surface portion (320).