Multi-Nozzle Printing Method for Near-Field Electrospinning Printing of Invisible Electrodes on PET Film

Abstract

It is well known that a conductive line with a width of a few micrometers is invisible to the naked human eye. Such invisible conductive lines could be used for various industrial purposes such as display applications. For this purpose, we will discuss the practical issues that arise in the near-field electrospinning printing method, while printing invisible conductive lines for transparent conductive film. The proposed method has the advantage of a rapid printing capability of more than 300 mm/s. However, a single nozzle has been commonly used, which could be a limitation of the process for industrial applications. The use of multi-nozzles for electrospinning printing has many difficulties from a practical point of view. In this study, we will discuss the practical issues such as cross talk and the uniformity of each printed line from each nozzle in the multi-nozzle printhead. For implementation of the transparent conductive film, we printed horizontal lines with a line spacing of 700 mm on polyethylene terephthalate (PET) film. The conductivity of the lines and the sheet resistivity are discussed in terms of line width, polymer-mixing ratio, and the transparency of the printed patterns. Even though we could not achieve low resistance because of the limited sintering temperatures that are used in order to avoid damage to the PET film, our preliminary study demonstrates that the proposed method could be potentially used in manufacturing transparent electronics.