Polymer micromould design and micromoulding process

Abstract To meet challenges towards miniaturisation, a new generation of moulding machines that use a separate screw plastication unit and a plunger injection system has been developed for fabrication of microcomponents down to milligram levels. In the present paper, studies have been carried out on micro tool designs to develop micromoulds that can meet the demand of the new machines. Micromoulding process studies were conducted using a Battenfeld Microsystem micromoulding machine with a maximum injection capacity of 1 cm3. It was found that for different polymer materials and product designs, different runner systems and mould structures need to be employed for improved melt flow and cavity fill. The runner weight was found to be significantly affected by the metering setting, especially when over metered settings were used. Control of the part weight however was more complicated and involved other processing parameters such as injection speed and mould temperature.