US Patent 7578954 Method for manufacturing microstructures having multiple microelements with through-holes

A method is provided for manufacturing microstructures of the type which contain a substrate and an array of protruding microelements with through-holes, which are used in penetrating layers of skin. The microelements are embossed or pressed into an initial substrate structure, which in some embodiments is formed from extruded polymeric material, and in some cases from two layers of polymer that are co-extruded. The through-holes are formed from filled through-cylinders of a second material that is removed after the embossing or pressing step; in other instances, the through-holes are left hollow during the embossing or pressing step.