Conductive Ink/Paste

Conductive Ink/Paste List

Conductive ink is a kind of ink that produces conductive printed matter. It is typically created by infusing graphite or other conductive materials into ink. It has a certain degree of conductivity and can be used for printing conductive dots or conductive lines. Gold-based conductive inks, silver-based conductive inks, copper-based conductive inks, and carbon-based conductive inks have been practically used for printed circuits, electrodes, electroplating bottom layers, keyboard contacts, printed resistors and other materials.

Classification:

• Metal nano-particle conductive ink: Metal nano-particle conductive ink mainly refers to the metal conductive ink made of nano-sized metal particles as the main carrier of electrical conductivity. Due to the nanometer size of metal particles, there are many advantages when used in printing and electronic manufacturing. Nano-metal materials are easy to make inks with different solution properties, so that they can be used in a variety of printing methods, such as ink-jet printing, flexible printing, gravure printing and screen printing with relatively high viscosity.
• Metal-organic decomposition inks: Metal-organic inks are mainly a class of metal-organic compounds that can be decomposed at lower temperatures, which are often called metal-organic precursors, which can form corresponding metal deposits after decomposition. In this way, researchers have developed metal-organic decomposition inks that can be used in printing electronics, such as gold, silver, copper and so on.
• Metal nanowire ink: Nanowires, also known as nanorods and nanofibers, have fibrous morphology. Typical nanowires should have a maximum diameter of less than 100 nm, and a length ranging from a few hundred nanometers to 50 microns. Metal nanowires not only have better electrical properties than metal nanoparticles because of their one-dimensional fibrous structure with high aspect ratio but also have a wider range of applications. For example, a silver nanowire grid is often used to make transparent conductive materials because of its high light transmittance, high conductivity and good mechanical stability.

Figure 1. SEM images of long silver nanowires ink.

• Ionic inks: Ionic inks mainly refer to the dissolution of inorganic metal compounds in appropriate solutions to form ionic inks, which can also be called inorganic metal precursor inks. After printing, the corresponding conductive patterns are formed through appropriate post-processing processes, such as heating, chemical reduction and chemical deposition. One of the characteristics of this kind of ink is that there are no particles in the ink solution. And the viscosity and surface tension of the ink solution can be well adjusted by various solvents to be suitable for all kinds of printing method.
• Carbon conductive inks: Compared with the above conductive inks with metal as the main conductive carrier, although the conductive properties of carbon conductive materials are relatively poor, they are also used in the production of conductive inks because of their low cost. Not only that but also because of the rich structure and various electrical properties of carbon materials, more and more carbon inks are used in the printing of electronic components. Some researchers have made wearable flexible supercapacitors using carbon fiber materials by weaving and screen printing. In addition, carbon electrodes are made by screen printing and then modified by CuO/ graphene. The device of non-enzymatic glucose sensors with high sensitivity, high selectivity and high stability can be prepared.

Figure 2. Schematic diagram of applying conductive ink on woven fabrics.

References

1. Ian E. Stewart. (2017) "Effect of Morphology on the Electrical Resistivity of Silver Nanostructure Films." ACS Appl. ter. Interfaces. 9(2): 1870-1876
2. Hong Hong. (2019) "UV Curable Conductive Ink for the Fabrication of Textile-Based Conductive Circuits and Wearable UHF RFID Tags." ACS Appl. Mater. Interfaces. 11(30): 27318-27326.