Pad printing of polymeric silver ink conductors on thermoplastic foils

Abstract

Purpose The aim of this study was to evaluate the feasibility of pad printing for producing electrical conductors and to define the factors affecting the print quality of polymeric silver ink conductors. Design/methodology/approach Polyethylene terephthalate (PET) film and polyphenylene oxide (PPO) compound film were used as substrate materials. Three different polymeric silver inks, marked A, B and C, were used and tested. Findings The results indicated that the important factors in the pad printing of silver ink conductors are the printing parameters and characteristics of the ink, pad, cliché and substrate. The interactions of these factors should be considered on a case-by-case basis. The sheet resistances of triple-pressed ink conductors varied between 20 and 110 mΩ/sq for 5.7- to 8.5-μm-thick conductors. Ink (B) had a higher sheet resistance than Ink (A) because of its lower silver particle content but also because of the shorter curing time and lower curing temperature. Ink (A) showed excellent adhesion on PET, and Ink (B) had moderate adhesion on PET without corona or plasma pre-treatments, but both inks adhered weakly on PPO compound. Both corona and plasma treatments raised adhesion of these two inks on all test substrates to the highest classification value, 5B. Originality/value This paper contains a survey and preliminary testing of the pad printing of polymeric silver ink conductors on flexible thermoplastic foils. Finally, the paper introduces the advantages and drawbacks of the technique.

Pad printing inks based on reduced graphene oxide and various cellulose binders: Rheological properties, printability and application in electrochemical sensors

“…The viscosity has to be low enough to transfer the ink from the pad onto the substrates. The ink sticks strongly on the pad if the viscosity is too high and is not transferred to the substrate 34 . The concentration of rGO in all samples was 1 wt%, and the effect of polymer component—ethylcellulose (EC)/cellulose acetate butyrate (CAB) concentration in the binder was explored.…”

“…The ink sticks strongly on the pad if the viscosity is too high and is not transferred to the substrate. 34 The concentration of rGO in all samples was 1 wt%, and the effect of polymer component-ethylcellulose (EC)/ cellulose acetate butyrate (CAB) concentration in the binder was explored. Viscosity values at different shear rates from the steady-state flow step test were measured, as shown in Figure 1a.…”

Investigation of inkjet printed path resistance in the context of manufacture and flexible application

“…These features of printed electronics allow researchers to develop areas connected with cheap and wearable electronics and easily integrate them into nonplanar objects. A few printing methods are being evolved in the field of electronics for different applications, namely, screen (Drabczyk et al , 2015), flexography (Alem et al , 2018), inkjet (Romeo et al , 2018; Futera et al , 2015), pad printing (Laine-Ma et al , 2016) and others (Tobjörk and Österbacka, 2011). They are used to manufacture radio frequency identification tags (Kim et al , 2018; Janeczek et al , 2016; Kim et al , 2013), humidity and chemical sensors (Cinti et al , 2018), touch elements (Salim and Lim, 2017; Faller et al , 2016) and transistors (Mizukami et al , 2018), etc.…”

Investigations of Printed Flexible pH Sensing Materials Based on Graphene Platelets and Submicron RuO2Powders

“…The possibility of low temperature processing made this technology advisable for applications using flexible materials, such as polymer foils [1], papers [2], and fabrics [3]. Electronic devices may be fabricated with printing processes, such as screen printing [4], flexography [5], ink-jet printing [6], gravure [7], or pad printing [8] which are well known from graphics industry. Thanks to novel materials suitable for electronics there are vast possibilities of fabrication of functional printings, such as conductive [9], resistive [10], dielectric [11], or sensitive layers [12].…”