Fabrication of a Quasicrystal Electrode at a Low Processing Temperature via Electrohydrodynamic and Transfer Printing for use in Multifunctional Electronics

Abstract

temperature or with heating at less than 60 °C for 1 h. This is not only one of the important conditions for determining the degree of aggregation of silver, but also for controlling the binding energy of silver or the density of silver that would be higher at the bottom. [18,19] We can also transfer print from the receiver to the adhesive tape, which results in a quasicrystal morphology (R a = nanoscale) with truly excellent flexibility and durability. [8][9][10]21,22] With this approach, we can fabricate flexible tiled circuits, water-proof light emitting diodes (LEDs) without any additional restricting condition, and this transferred electrode would be freestanding, attached to various uneven interface operated LEDs. A merit of this method is that, without adaptive printing on the 3D circuits, we can apply the electrodes on 3D structures by using the projected electrodes.Furthermore, these electrodes are connected to each other to produce long-ranged line pattern arrays, and the soldering disconnection of a wire can be achieved with the nonpatterned residue of the adhesive region.Based on this study, e-NDP can be considered as a new method, which is different from the existing EHD method that needs the condition of a nozzle-to-substrate distance of less than 500 µm for the near-field electrospinning jet. In the existing EHD method, only the Si wafer and the glass substrate through which charged electrons can be transferred to the ground and only their parts in which the solution is aligned after taylorcone formation at the nozzle tip have been used. [11][12][13]15,16,20] We propose a patterning mechanism that offers a closer nozzleto-substrate distance than conventional EHD printing operating at less than 100 µm to easily charge the electron moving nozzle with ground (GNR) in spite of using an insulated PET substrate (Figure 1a,b, inset). This method can be used to fabricate a silver micropatterned electrode that can be printed in ≈4 s (20 mm s −1 is the optimized speed for formation of the electrode) with a 70 mm parallel line pattern. This electrode resolution was controlled by increasing the printing speed ( Figure S1a,b, Supporting Information). Figure 1 shows a schematic to fabricate a silver micropatterned electrode using the e-NDP process. The first step is to pattern a silver trace after printing the e-NDP solution on a PET substrate coated with silver trifluoroacetate (STA) (18 wt%) dissolved in volatile tetrahydrofuran (THF). The second step is to reduce the silver trace pattern using a hydrazine monohydrate solution with ethyl alcohol (30 wt%). This solution is overpatterned on the position of the silver trace at a low temperature of 60 °C for 1 h. As the experimental equipment has a function of automatically performing overpatterning, misalignment could not occur during same-trace-position printing.Pattern formation is a complex technology that has resulted from a collaborative effort by researchers in chemistry and industrial processing. Bath processing has been implemented by a myriad of organiza...

Skinlike Disposable Tattoo on Elastic Rubber Adhesive with Silver Particles Penetrated Electrode for Multipurpose Applications

“…Figure a shows a schematic of the confined-area dissolving of the adhesive elastic layer from a silver precursor with an optimized condition of electro-hydrodynamic narrow-nozzle-to-substrate distance printing (e-NDP) . The elastomeric adhesive rubber was coated on an eco-flex (adhesive/eco-flex) with a bar-coater (Figure S1).…”

“…The pattern on the PET substrate observed under XPS shows two peaks at 369 and 375 eV. When using the penetrated electrode in the elastic adhesive layer, the XPS results for the Ag-PEA tattoo show a somewhat increased binding energy in Ag 3d 3 and Ag 3d 5 (1 eV) . Therefore, using this as a buffer for the patterned adhesive substrate has a confining effect of the Ag particle percolation network with elastic properties.…”

“…Figure 1a shows a schematic of the confined-area dissolving of the adhesive elastic layer from a silver precursor with an optimized condition of electro-hydrodynamic narrow-nozzleto-substrate distance printing (e-NDP). 24 The elastomeric adhesive rubber was coated on an eco-flex (adhesive/eco-flex) with a bar-coater (Figure S1). When patterning on the adhesive substrate, we can produce the patterning on a tunable line width obtained from a prepenetrated silver salt electrode with a controlled pattern speed and nozzle-to-substrate distance (Figure 1b), (Figure S2).…”