By TDK Corporation 102
TDK's FLECLEAR® family of thin, transparent conductive film, called Ag-stacked film, utilizes a proprietary silver alloy material as its conductive layer and is deposited onto a film substrate. FLECLEAR Ag-stacked film achieves low resistance and excellent flexibility while maintaining high transmittance exceeding that of ITO (indium tin oxide) films. ITO films have traditionally been used as the mainstream transparent electrode material, but face challenges, such as when the film thickness is reduced to increase transmittance, the surface resistivity (sheet resistance) increases and conductivity deteriorates. Resource availability also becomes an issue with ITO films, as indium is a rare metal material that poses risks in terms of stable supply and price. Additionally, as ITO films used thicker conductive layers to reduce the surface resistance, optical properties such as yellowing and haze began to be impacted immensely.
FLECLEAR was developed using an Ag (silver) alloy, as silver features the highest conductivity among metals. The Ag-alloy material is sandwiched between two protective layers and is uniformly deposited onto the film substrate using an advanced sputtering method, allowing for high conductivity, high transmittance in the visible light region, and high reflectivity in the infrared (IR) region. By virtue of the film's high reflectance in the IR region, the conductive layer's material characteristics provide for a high heat shielding effect, cutting heat rays and conserving energy when used for IR blocking in windows of buildings or automobiles. TDK’s Ag-stacked film also features a reduction in surface resistance – down to 1/5 or less than that of ITO films – and performance stability through repeated mechanical bending.
Thanks to the low resistance and high transmittance of TDK’s Ag-stacked film, along with its excellent storage reliability, thermal stability, and flexible nature, the film can be used in various applications including flexible displays, wearable devices and lighting, OPV (organic photovoltaic) cells, light control glasses or films, and transparent antennas.