The Materials of Flexible Printed Circuit (FPC)
Mainly consisted with 4 parts: Copper Film, Cover Film, PI Striffener Film, Adhesive Sheet
Specific materials involved are as below:
Copper: can be ED-Electro Deposit or RA-Rolled Annealed (which is usually used for the FPC for mobile). Usually 1oz or 1/2 oz thickness (copper thickness: 1/2oz =0.7 mil=0.018mm)
Base Film: normal material is PI (polyimide). Usually 1mil or 1/2 mil thickness.
Adhesive: thickness is up to customers’ request. usually epoxy resin thermosetting adhesive
Cover Film: Used for surface insulation. Normal material is PI (polyimide). usually 1mil or 1/2 mil thickness.
PI Stiffener Film: Enhance the mechanical strength of FPC. Usually 5mil or 9mil thickness.
Release Paper: To avoid the adhesive stained
Stiffener Material: Usually use PI, FR-4 and steel sheets
Adhesive sheet between layers: 1mil epoxy resin thermosetting adhesive
Note: 1mil =1/1000in=0.025mm. 1mim=40mil
So, for each single layer Flexible Printed Circuit (FPC), the thickness is about: 0.5mil cover film + 0.5mil adhesive + 1/2oz copper +
0.5mil adhesive + 0.5 base film = 2.7mil=0.0675mm
–Posted by Bright PCB Technology Co., Ltd