Evaluation of the Sheet Resistance of Inkjet-Printed Ag-Layers on Flexible, Uncoated Paper Substrates Using Van-der-Pauw’s Method

With the growing significance of printed sensors on the electronics market, new demands on quality and reproducibility have arisen. While most printing processes on standard substrates (e.g., Polyethylene terephthalate (PET)) are well-defined, the printing on substrates with rather porous, fibrous and rough surfaces (e.g., uncoated paper) contains new challenges. Especially in the case of inkjet-printing and other deposition techniques that require low-viscous nanoparticle inks the solvents and deposition materials might be absorbed, inhibiting the formation of homogeneous conductive layers. As part of this work, the sheet resistance of sintered inkjet-printed conductive silver (Ag-) nanoparticle cross structures on two different, commercially available, uncoated paper substrates using Van-der-Pauw’s method is evaluated. The results are compared to the conductivity of well-studied, white heat stabilised and treated PET foil. While the sheet resistance on PET substrate is highly reproducible and the variations are solely process-dependent, the sheet resistance on uncoated paper depends more on the substrate properties themselves. The results indicate that the achievable conductivity as well as the reproducibility decrease with increasing substrate porosity and fibrousness.

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Fabrication and characterization of resistive double square loop arrays for ultra-wide bandwidth microwave absorption

Scientific Reports ◽

10.1038/s41598-021-91868-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ji-Young Jeong ◽

Je-Ryung Lee ◽

Hyeonjin Park ◽

Joonkyo Jung ◽

Doo-Sun Choi ◽

...

Keyword(s):

Sheet Resistance ◽

Manufacturing Process ◽

End Milling ◽

Milling Process ◽

Wide Bandwidth ◽

Machined Surface ◽

Array Pattern ◽

Micro End Milling ◽

Array Structures ◽

Printing Processes

AbstractMicrowave absorbers using conductive ink are generally fabricated by printing an array pattern on a substrate to generate electromagnetic fields. However, screen printing processes are difficult to vary the sheet resistance values for different regions of the pattern on the same layer, because the printing process deposits materials at the same height over the entire surface of substrate. In this study, a promising manufacturing process was suggested for engraved resistive double square loop arrays with ultra-wide bandwidth microwave. The developed manufacturing process consists of a micro-end-milling, inking, and planing processes. A 144-number of double square loop array was precisely machined on a polymethyl methacrylate workpiece with the micro-end-milling process. After engraving array structures, the machined surface was completely covered with the developed conductive carbon ink with a sheet resistance of 15 Ω/sq. It was cured at room temperature. Excluding the ink that filled the machined double square loop array, overflowed ink was removed with the planing process to achieve full filled and isolated resistive array patterns. The fabricated microwave absorber showed a small radar cross-section with reflectance less than − 10 dB in the frequency band range of 8.0–14.6 GHz.

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High-Resolution Electrohydrodynamic Printing of Silver Reactive Inks

MRS Advances ◽

10.1557/adv.2016.482 ◽

2016 ◽

Vol 1 (34) ◽

pp. 2409-2414 ◽

Cited By ~ 1

Author(s):

Christopher Lefky ◽

Galen Arnold ◽

Owen Hildreth

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Inkjet Printing ◽

Solid Metal ◽

Electrohydrodynamic Printing ◽

Annealing Step ◽

Scale Structures ◽

Fine Resolution ◽

Printing Processes ◽

Continuous Material

ABSTRACTNano-inkjet printing using an Electrohydrodynamic's (EHD) pulsed cone-jet approach has the potential to bring affordable additive manufacturing to the micro and nanoscale. Ink technology is a major limitation of current EHD techniques. Specifically, most EHD printing processes print either nanoparticles or polymers. The materials are structurally weak and often have poor electrical or mechanical properties. For example, printing nanoparticles effectively creates a cluster of nanoparticles that must be sintered to create a continuous material. To address these issues, we have been adapting reactive inks to work with an EHD pulsed cone-jet. Specifically, we demonstrate that silver micron-scale structures can be printed using an EHD pulsed cone-jet regime. These inks produce solid structures without sintering steps and with good electrical properties.1,2 This work shows that reactive ink chemistries can be combined with EHD printing to produce fine-resolution features consisting of solid metal without an annealing step.

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The Study on Color Print Quality Attributes of In-Mold Roller Using Digital Inkjet Printing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.262.340 ◽

2012 ◽

Vol 262 ◽

pp. 340-344 ◽

Cited By ~ 2

Author(s):

Chang Lang Chen ◽

Mei Chun Lo ◽

Yun Ti Su ◽

Yu Tung Chang

Keyword(s):

Inkjet Printing ◽

Screen Printing ◽

Print Quality ◽

Gravure Printing ◽

Color Gamut ◽

Printing Process ◽

Study Results ◽

Pet Film ◽

Printing Processes ◽

Potential Use

The In-Mold Roller is a revolutionary printing process by which objects are 3D decorated. The products decorated by In-Mold Roller are protected from water and fading. These kinds of decorations strongly increase the beauty, desirability and value of the objects. The In-Mold Roller is now using either of gravure printing and screen printing to print PET film. However, there are some problems with these two techniques. This research is to investigate the potential use of combining In-Mold Roller with digital inkjet printing in 3D decoration, e.g. in personalized printing services. The study results found show that digital inkjet printing to the PET film and then transfer to the ABS, the solid ink densities (SIDs) of primaries would increase. The tone values increases (TVIs) from highlight and middle (around 0~60%) were generally higher than those in shadows. The shapes and sizes of color gamut were also varied according to different kinds of digital UV inkjet printing processes. Moreover, after transferred, the color gamut became smaller.

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PAPER SUBSTRATES FOR INKJET PRINTING OF UHF RFID ANTENNAS

10.37763/wr.1336-4561/65.1.025036 ◽

2020 ◽

Vol 65 (1) ◽

pp. 025-036

Author(s):

Juraj Gigac ◽

Mária Fišerová ◽

Maroš Kováč ◽

Monika Stankovská

Keyword(s):

Inkjet Printing ◽

Uhf Rfid ◽

Rfid Antennas ◽

Paper Substrates

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Comparison of thermal transfer and inkjet printing of UHF RFID tag antennas on paper substrates

Wood Research ◽

10.37763/wr.1336-4561/66.1.7184 ◽

2021 ◽

Vol 66 (1) ◽

pp. 71-84

Author(s):

JURAJ GIGAC ◽

MÁRIA FIŠEROVÁ ◽

SVETOZÁR HEGYI

Keyword(s):

Inkjet Printing ◽

Uhf Rfid ◽

Rfid Tag ◽

Thermal Transfer ◽

Paper Substrates

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Solution-processed perovskite thin-films: the journey from lab- to large-scale solar cells

Energy & Environmental Science ◽

10.1039/d1ee02018h ◽

2021 ◽

Author(s):

Zahra Saki ◽

Mahdi Malekshahi Byranvand ◽

Nima Taghavinia ◽

Mayank Kedia ◽

Michael Saliba

Keyword(s):

Thin Films ◽

Solar Cells ◽

Inkjet Printing ◽

Large Scale ◽

Spray Coating ◽

Solution Processed ◽

Slot Die ◽

Deposition Techniques

This review explores perovskite crystallization in scalable deposition techniques, including blade, slot-die, spray coating, and inkjet printing.

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Multi-Layer Inkjet Printing of Ag Nanoparticle Inks and Its Sintering with a Near-Infrared System

International Journal of Precision Engineering and Manufacturing ◽

10.1007/s12541-018-0037-8 ◽

2018 ◽

Vol 19 (2) ◽

pp. 303-307 ◽

Cited By ~ 4

Author(s):

Ki-Hak Sung ◽

Janghoon Park ◽

Hyunkyoo Kang

Keyword(s):

Inkjet Printing ◽

Near Infrared ◽

Ag Nanoparticle ◽

Nanoparticle Inks

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Inkjet Printing of PEDOT:PSS Based Conductive Patterns for 3D Forming Applications

Polymers ◽

10.3390/polym12122915 ◽

2020 ◽

Vol 12 (12) ◽

pp. 2915

Author(s):

Indranil Basak ◽

Gudrun Nowicki ◽

Bart Ruttens ◽

Derese Desta ◽

Jeroen Prooth ◽

...

Keyword(s):

Sheet Resistance ◽

Inkjet Printing ◽

Indium Tin Oxide ◽

Thermoplastic Polyurethane ◽

Weather Conditions ◽

Touch Sensor ◽

Drop On Demand ◽

Vacuum Forming ◽

The Right ◽

Time Stretching

This paper presents the formulation, inkjet printing, and vacuum forming of a conductive and stretchable polymer, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), ink on a stretchable and transparent thermoplastic polyurethane (TPU) substrate. The formulation of the conductive and stretchable ink is achieved by combining PEDOT:PSS with additional solvents, to achieve the right inkjet properties for drop-on-demand (DoD) inkjet printing. A conductive pattern can be printed from the 21 µm orifice on a flexible and stretchable TPU substrate, with a linewidth down to 44 µm. The properties of the printed pattern, in terms of sheet resistance, morphology, transparency, impact of weather conditions, and stretching are investigated and show sheet resistances up to 45 Ohm/sq and transparencies as high as 95%, which is comparable to indium tin oxide (ITO). Moreover, in contrast to ITO, one-time stretching up to 40% can be achieved, increasing the sheet resistance up to 214 Ohm/sq only, showing the great potential of this ink for one-time stretching. Finally, as a proof of this one-time stretching, the printed samples are vacuum formed around a 3D object, still showing sufficient conductivity to be applied as a capacitive touch sensor.

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