Pattern size tolerance of reverse offset printing: a proximity deformation effect related to local PDMS slipping

Abstract

We investigated the shape integrity of silver nanoparticle ink patterns formed by reverse offset printing, focusing particularly on the proximity effect of neighbouring patterns due to the local deformation of a polydimethylsiloxane (PDMS) blanket during contact with a hard cliché. We performed printing tests using a cliché having circular patterns with smaller neighbouring circles located at various distances (2–20 µm), and the results revealed that as we decrease the thickness of PDMS and the inter-pattern gap distance, and as we increase the printing indentations, the shape integrity of the printed pattern was worsened. A complementary numerical simulation of PDMS deformations suggested that the pattern distortion during the contact with clichés was caused by the horizontal deformation of PDMS during the printing, which becomes a significant burden when the uplifted region of PDMS is closer to the gap distance of each pattern. Our analysis further indicates that during printing, there is slipping of the ink at the PDMS interface. In addition, we examined the effects of a synchronization mismatch in a roll-to-sheet printing on the pattern size tolerance. The magnitude of the size distortions was severely influenced not only by the mismatch ratio but also by the nip width. This result verifies the scraping of the ink accompanied by the slipping of the PDMS during the printing process, and thereby determines the size tolerance of printed patterns in reverse offset printing. Finally, we discuss the optimization of process parameters to ensure the size integrity of reverse offset printing.

Printed Electronics Technologies for Additive Manufacturing of Hybrid Electronic Sensor Systems

“…The blanket cylinder slightly deforms when contacting the cliché as well as during printing, due to its softness, which can again result in artifacts in the pattern formations (size‐tolerance problem), as studied by Kusaka et al. [ 208 ] In addition, they observed the slipping of ink between the blanket cylinder and the substrate. These effects can lead to registration errors, which are a major degrading factor for high‐resolution multi‐layer printing, in particular, when neighboring patterns are closely located.…”

Patterning defects in high-speed reverse offset printing: lessons from contact dynamics

“…In addition, the structural integrity of interdigit patterns with a linewidth of 20 μm was maintained for all directions, even at δ = 30 μm. This result guarantees possible further optimisations of high-speed reverse offset printing for fine patterns; however, a careful pattern design avoiding the proximity deformation effect due to local PDMS slipping is required [27].…”

“…The quality of printed patterns is a critical aspect of reliable printed electronics. There are various defect types such as pinhole-type open defects due to the dewetting of the applied ink layers, particle contaminations, bottom-contact defects due to printing indentations [28,29] and pattern distortions due to PDMS slipping [27]. This study was focused on defects that are uniquely found in the high-speed patterning via reverse offset printing.…”

Development of a Strain Sensor Matrix on Mobilized Flexible Substrate for the Imaging of Wind Pressure Distribution

“…The industrialization of such large-area sensors requires an improved manufacturing process that can efficiently process the large areas. Thus, printing technology was developed to create functional layers in the atmosphere without the use of photoresists and the etching process [10][11][12].…”