Specialty conductive inks can be printed onto flat plastic substrate films using conventional screen, gravure or pad printing techniques. After drying, the plastic film can then be formed into shape using heat and pressure, and the printed conductive ink traces will follow the contour of the molded part. Even with sharp bends and deep draw sections in the molded part, the conductive ink traces will maintain conductivity. Electronic circuits fit easily into molded parts without the additional step of attaching a circuit to a molded part.
Conductive Compounds, http://www.conductivecompounds.com