This study explores the effect of the wash-out of conductive inks used during the in-mold electronic process. The influence of processing conditions and design parameters on wash-out areas during overmolding is analyzed. Using a comprehensive design of experiments approach, factors like the gate type, cavity thickness, melt temperature, injection rate, and mold temperature were evaluated. Three gating types, namely, edge, fan, and submarine, were considered. From the statistical analysis, it was demonstrated that the choice of gating type is the most important factor. Cavity thickness is the second most important factor for all three gating types. Reducing cavity thickness and raising melt temperatures generally led to a decrease in wash-out (WO), whereas the effect of injection rate varied depending on the gating method used. Adjusting mold temperature also produced favorable results, emphasizing the importance of ink-to-substrate adhesion. Simulation studies revealed the relationship between shear rate and wash-out area, underscoring the need to control injection parameters. These findings stressed the importance of meticulous design and processing to minimize wash-out defects, thus advancing in-mold electronic technology and meeting market demands for complex electronic parts.
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