What is polyimide PCB?
Most ordinary PCBs use FR4 materials to form rigid PCBs. Polyimide material is the main material that constitutes flexible PCB. It has the characteristics of radiation resistance, high temperature resistance, high tg, high td, high flexibility and high electrical properties.
Comparison between polyimide resin and FR-4
| Property |
Polyimide |
FR4(High Tg) |
| Dk |
4.2 |
4.2~5.2 |
| Dk Stability |
High |
uncontrolled |
| Df (1MHz) |
0.01 |
0.023 |
| Tg℃ |
250 |
150~170 |
| Td(onset) |
370~380 |
310~320 |
| T260(min) |
>60 |
>60 |
| T288(min) |
>60 |
>30 |
| ANTI CAF |
Yes |
DEPENDS |
From the above figure, we can conclude that compared with FR4, polyimide material has better radiation resistance and high TG (the higher the TG, the lower the possibility of polyimide resin falling off and the more reliable it is) , high td resistance, and the dielectric constant is very stable.
Not only that, polyimide materials have more reliable characteristics than FR4. Polyimide PCB has high temperature resistance (260°C), and the thermal decomposition temperature has also reached 360°C. If FR4 is allowed to heat up from 20°C to 150°C, the PCB will fail after 1000 cycles. The PCB made of polyimide material can reach 5,000 cycles. If exposed to high temperatures above 220°C, FR-4 will fail after 10 cycles, while polyimide PCB can withstand 100 cycles.
Applications of polyimide PCB
1. Various consumer electronic products: High flexibility and bendability allow devices to be made smaller. Common ones include smart bracelets, mobile phones and computers, etc.
2. High-temperature applications: The high-temperature resistance of polyimide materials allows polyimide PCBs to be widely used in probe control systems of industrial machines, aging test equipment, high-power power supplies, etc.
3. Military and high-precision small-volume instruments: Not only because polyimide PCB has higher flexibility and bendability, higher reliability and resistance to extreme environments, polyimide PCB also Can be widely used in high-standard fields.
4. Aerospace satellite application: Polyimide PCB has radiation resistance and high electrical properties, and can perform product functions more stably in the aerospace field.
Polyimide PCB is usually called flexible PCB, because the main material of flexible PCB is polyimide resin, which is resistant to radiation, high temperature, high tg, high td, high flexibility, and high electrical characteristics. Polyimide PCB can be used in many professional fields. be utilized.
