The basic structure of FPC flexible circuit board is as follows:

Copper foil: It is basically divided into two types: electrolytic copper and rolled copper. The commonly used thicknesses are 1oz 1/2oz and 1/3 oz

Substrate film: There are two common thicknesses: 1mil and 1/2mil.

Adhesive (Follower): The thickness depends on customer requirements.

Film covering

Cover film protective film: used for surface insulation. The commonly used thicknesses are 1mil and 1/2mil.

Adhesive (Follower): The thickness depends on customer requirements.

Release paper: Avoid adhering foreign objects before pressing the adhesive; Easy to work.

PI Stiffener Film

Strengthening board: Enhance the mechanical strength of FPC to facilitate surface installation and operation. The common thickness range is from 3mil to 9mil.

Adhesive (Follower): The thickness depends on customer requirements.

Release paper: Avoid foreign object adhesion before pressing.

EMI： Electromagnetic shielding film, protecting the circuit board from external interference (strong electromagnetic area or susceptible area)