Conductive Inks in PCBs and Printed Electronics

With the increasing popularity of wearable devices, flexible displays, medical sensors and flexible hybrid electronics (FHE), the use of conductive ink in PCBs and printed electronics is also on the rise. Unlike traditional rigid PCBs etched with copper foil, conductive inks can be directly applied to materials such as PET, polyimide, TPU, textiles or glass, just like printed circuits, to achieve conductive pathways.

This article will start from the most basic content and take you to understand what conductive ink is, what it’s made of (such as conductive fillers and resin binders), and what common types there are. At the same time, the article will also discuss their advantages and disadvantages, as well as the circuits or PCB processes they are suitable for.

Next, it will compare the traditional PCB manufacturing method (subtractive etching) with the printed electronics process using conductive inks (additive manufacturing), making it easier for you to understand how it helps circuits become thinner, lighter, more flexible, and more suitable for the design of future smart devices.

What is Conductive Ink?

Conductive ink is an ink that can be printed and conduct electricity. It contains metal powder or carbon particles, and these conductive materials are uniformly dispersed in the liquid medium. When this ink is printed onto substrates such as PET, PI, glass or fabric, and then heated or cured, conductive circuits can be formed.

Unlike ordinary colored inks, conductive inks are not used for visual decoration, but for conducting electricity. It is more like a printed circuit material. Nowadays, it is widely applied in fields such as flexible circuits, RFID antennas, membrane switches, medical electrode patches, printed sensors, and flexible hybrid electronics (FHE).

Among the numerous conductive inks for printed electronics, silver conductive ink is the most commonly used because of its best conductivity, high stability and strong adaptability with different manufacturing processes.