Development of a modularized and sectioned micromold system for microinjection molding of plastic microstructured surfaces with complex features

In this study, a novel modularized and sectioned micromold system (MSMS) is proposed and developed for the replication of various plastic microstructured surfaces with complex features. The developed MSMS consists of sectioned micromold modules (SMMs), each of which has unique cross-sectional microfeatures on one surface. Together, these form the entire micromold surface. After multiple SMMs are precisely prepared, the final MSMS for a micromolding application can be efficiently constructed in various combinations by assembling several SMMs. In order to exemplify the developed MSMS, three prototypes of microstructured surfaces with complex microscale features were realized. These include (i) a complex microstructured surface, (ii) multi-level microstructured surface and (iii) oblique microstructured surface. The SMMs for each case were precisely manufactured using deep x-ray lithography and nickel electroforming. The MSMS for the replication of the microstructured surfaces was then obtained by assembling the fabricated SMMs. Finally, three kinds of prototypes were replicated with a microinjection molding process utilizing the constructed MSMS, verifying the usefulness of the present micromold system in various applications such as the fabrication of functional surfaces for optical, microfluidic and biomedical microsystems.