What Is The Dielectric Constant
Feb 17, 2022
Since fpc materials are divided into two types, polyimide (Polyimide) and polyester (Polyester), we have to separate them here.
1. Polyimide
Polyimide (PI for short) is the most commonly used thermally cured insulating material in flexible circuit processing. Material thicknesses typically range from 12.5 μm (0.5 mil) to 125 μm (5 mil). Divided into glued and glueless, the dielectric constant of glued is 3.5, and the dielectric constant of no glue is 3.3.
2. Polyester
Polyester is made of polyethylene terephthalate (PET for short, polyethylene terephthalate). The thickness range of its application to flexible boards is generally 25μm (1mil) ~ 125μm (5mil). It has the same excellent softness and electrical properties as Polyimide.
However, its dimensional stability during the manufacturing process is slightly worse than that of Polyimide. In addition, it has poor tear resistance and is more sensitive to welding temperature. Its dielectric constant is 3.4.
The above is the dielectric constant of the fpc flexible board compiled by the editor, I hope it will be helpful to you
