在高分子材料中，表面潤濕特性對材料的應用是非常重要的性質，表面改質能使材料的應用範圍變得更加廣泛。而在自然界以及我們的生活周遭有著許多動物及植物有著超疏水表面的特殊性質，也就是自清潔及異向性潤濕的表面，例如:蓮花的葉面、鳥類的羽毛、孑孓的腳等，我們從這些例子中取得靈感，用人工的方式來製作疏水表面，再進一步去實驗來證實它的特性。本實驗用鹽酸蝕刻以及沸水處理鋁合金試片，使試片表面形成微奈米等級的粗糙表面，再以含氟改質劑浸泡之，以增加表面的疏水特性，使水滴在鋁合金表面上的任何一個方向皆能自由滾動，製作出仿自然界的超疏水表面，接著再利用雷射於試片表面刻畫出不同型式的溝槽，實驗結果發現溝槽外兩側為超疏水特性，而溝槽內部為親水，所以水滴一旦滴在溝槽中便會沿著溝槽流動，且在垂直溝槽方向上有吸附力，用以仿效稻米葉的表面型態，並觀察不同大小的水滴，在平行刮痕線條方向和垂直刮痕線條方向上，所量測的接觸角有什麼變化，此現象稱之為異向性，並加以利用，將刮痕刻畫成要的圖形來做成流道，可以將水滴導流至需要的地方，這個現象可以用在微量流體的導流和自清潔效應上。
Superhydrophobic surfaces have attracted much interest because of the potential applications in many industrial processes as well as in daily life. Combining surface roughness on both the micro- and nanoscales with a low-surface-energy material is the key to obtaining superhydrophobicity. The superhydrophobic surfaces with anisotropic wetting phenomena have also drawn a great amount of attention recently.
In this paper, we present a simple method for realizing anisotropic wettability and for controlling the mobility of microliter-sized droplets on superhydrophobic Al alloys. A designed path line is created on the prepared superhydrophobic surface using a laser irradiation process. We achieved both static anisotropic wettabilities (e.g., different static contact angles in different directions) and dynamic anisotropic wettabilities (different sliding angles in different directions) on the patterned superhydrophobic surface. The micro-liter droplets move spontaneously toward a preset route on our patterned superhydrophobic surface. Furthermore, the use of commercially available raw materials and the simple fabrication process makes it possible to apply such surfaces industrial applications.
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