Impact of Structural Adhesive Hybridization Strategy on the Performance of In‐Mold Electronics Devices Across Thermoforming and Injection Molding

In‐mold electronics (IME) combines printed electronics with in‐mold decoration (IMD) to integrate circuits into complex applications. It has been demonstrated that adhesives impact the film deformation, requiring adjustments in amount and the deposition place based on the local deformation to which they are subjected. However, since thermoforming is not the final step, it remains unclear whether these adjustments impact the functionality of the device in the subsequent process. This study investigates the influence of structural adhesive placement and amount on the functionality of printed circuits throughout the complete IME manufacturing process. Samples were hybridized with the proposed adhesive adaptation and subjected to thermoforming and injection molding. Electronic characterization was conducted before and after each process step. The results demonstrate that the adjusted adhesive application does not negatively impact circuit functionality, with some devices exhibiting improved performance. These findings offer a reliable approach to optimize adhesive application in IME production, thereby enhancing the yield of functional devices.