Although the performance of FPC depends on many factors, the main material plays a key role in it.  So, what are the constituent materials of the FPC? 

In the structure of the FPC, the constituent materials are composed of flexible copper clad laminate (FCCL), cover film, adhesive film and so on.

Flexible Copper Clad Laminate (FCCL): Common sheet films of flexible copper clad laminates include polyimide film (PI), polyester (PET), polyethylene naphthalate (PEN), liquid crystal display polymer ( LCP) and other polymer material plastic films.  In FPC, the copper clad laminate mainly plays the role of three levels of conductivity, insulation layer and support point.

Cover film: It is composed of chemical plastic film and adhesive.  The function of the cover film is to protect the conductive part of the flexible circuit that has been completed.  It has different sheet film and adhesive types and thickness specifications.

Adhesive film: It is formed by pouring adhesive on both sides or one side of a substrate film.  There are also adhesive films with a pure adhesive layer without a substrate.  The adhesive film has different adhesive types and thickness specifications.  Adhesive film is used for interlayer bonding and insulation of multilayer boards.

PCBmanufacturer talk Ordinary FPC is mainly composed of two materials: base material + cover film.  The base material is mainly composed of PI or PET + glue + copper.  PI is a polyimide insulating resin material, which is characterized by high temperature resistance and good bending performance.  PET is polyester insulating resin material, but its characteristics are just opposite to PI, so it is used by few FPC manufacturers.