Flexible printed circuit board -- Hitech Circuits Flexible printed circuit (FPC) is a technology developed by theUnited Statesto develop aerospace rocket technology in the 1970s. It is high reliability, excellent deflection made by polyester film or polyimide as a substrate material. A flexible circuit is formed by embedding a circuit design in a thin, flexible plastic sheet that is flexible, allowing a large number of precision components to be stacked in a narrow and limited space. This circuit can be bent and folded at will. Flexible has the characteristics like light weight, small size, good heat dissipation, easy installation, etc