Evaluation of vacuum venting and variotherm process for improving the replication by injection moulding of high aspect ratio micro features for biomedical applications

Vacuum venting has been reported to be an effective technique in replicating microfeatures by micro injection moulding. High surface-to-volume ratio and reduced dimensions of micro-parts promote the instantaneous drop of melt temperature and consequently lead to incomplete filling. This study aims to investigate the effects of variotherm process, cavity evacuation and their interaction on the production of a microfluidic filter for biomedical applications, revealed the importance of these moulding technologies in enhancing part filling and the replication quality for high aspect ratio features.