Flexible Copper-clad laminate is the sub-section of the Flexible PCBs. These categories are made by considering the mechanical rigidity of copper-clad laminates. Other than the FCCL, there is another alternative called RCCL, or rigid Copper-clad laminate.

FCCL is the base laminate of the Flexible PCB. As part of the primary material, FCCL plays a major in the flexibility of the product and other functions. Also, FCCL consists of layers of copper foil and polyimide, which are used as an electrical conductor and insulator for the PCB.

Difference Between Adhesive FCCL (3L-FCCL) and Non-Adhesive FCCL (2L-FCCL）

The primary difference between Adhesive and non-adhesive FCCL is that the adhesive FCCL is laminated in between the PI (polyimide film) and Copper, whereas the non-adhesive is not.In accordance with the depiction of this image, 3L-FCCL is also called adhesive FCCL while 2L-FCCL is also called non-adhesive FCCL.

Another major difference is that the non-adhesive FCCL is more costly than the FCCL adhesive. In regards to applications and production capabilities, there are major differences between them based on the manufacturing requirements. Whereas the FCCL with adhesive is best for producing the following types of flexible PCBs:

Single-sided FPCB.
Simple Flexible Keyboards.
Double-sided FPCB.

The non-adhesive FCCL is best for producing the following flexible PCBs:

Multilayer circuit boards.
High-density SMDs.
High-density interconnect PCBs.
Impedance-controlled PCBs.
Rigid-flexible circuit boards.

Since the price of 2L-FCCL is higher and the output is not enough to supply the demand for high-level soft boards, so many international manufacturers put 2L-FCCL into production, however, the output speed is slow and the yield rate is not high.