Speakers

This paper presents the highly flexible Ag nanowire TCF, so called "Flexionet" film, which is prepared by roll-to-roll photonic welding process. Photonic welding is a well-known process that can weld Ag nanowire contacts to stabilize and improve electric properties and mechanical stabilities. 1-2 However, such technology was only demonstrated in a laboratory scale with many restrictions. Specially designed Ag nanowire ink and welding process can efficiently weld nanowire contacts during roll-to-roll coating process. The resulting film shows excellent bending properties and improved electric resistance without affecting the optical properties.

Figure 1 illustrates the typical welding process of Ag nanowire TCF. The wire-wire contacts are weak physical contacts where ~1 nm polymer layer present. Upon the absorption of intense visible light, the wires are slightly melted from the surface and eventually forming solid contacts. Due to the stablized wire contacts, the mechnical property, e.g. bending stability, and electric resistance are improved. We have tested the bending stability with 1 mm bending radius and the resulting resistance change after 500,000 times of bending was measured less than 10% from the initial value. The resistance was also lowered more than 30% from the un-welded films.

Dr. Sang Ho Kim is the founder and CEO of N&B in Daejeon, Korea. In addition, he has been a professor at Kongju National University working on various nanomaterials for printed and flexible electronics. Before joining the academic position, he worked more than 10 years in the commercial R&D part including LG Chem, Korea and Hewlett Packard Labs, Palo Alto, CA. Currently he is working and Ag nanowire technology for flexible transparent conductive film applications.