Hierarchically structured membranes manufactured by inkjet technology

Membranes with micro pores smaller than 30 μm are required in many micro systems dedicated to biological and chemical applications. However, the challenges of manufacturing these membranes rise with decreasing pore sizes. Similar requirements have to be met regarding the dependence of flow resistance and membrane thickness. Currently, the mechanical stability of these membranes has to be improved to establish appropriate industrial micro systems fabrication.The paper outlines a new route to manufacture those micro membranes based on inkjet as a digital fabrication technology.Single droplets of a qualified liquid are inkjet printed onto a temporary supporting substrate. These droplets are used as molds for the pores of a thin polymer membrane. The macroscopic membrane structure is made by casting a curable polymer solution onto the droplet pattern. The digital fabrication character of the patterning process enables the manufacturing of hierarchically structured membranes as a variable pattern of pores and support structures in one single patterning step. This technology allows free three-dimensional membrane design.