Pattern formation in slot-die coating

Kasischke, Maren; Hartmann, Simon; Niermann, Kevin; Smarra, Marco; Kostyrin, Denis; Thiele, Uwe; Gurevich, Evgeny L.

Research article (journal) | Peer reviewed

Abstract

We experimentally study the occurrence of pattern formation during the slot-die coating of partially wetting liquids onto Polyethylenterephthalat (PET)-substrates outside the coating window. The experimental investigation is supported by numeri- cal simulations of a dynamical model. Our results demonstrate that beyond a critical coating speed the deposition of homogeneous coating layers undergoes an instabil- ity resulting in the self-organized emergence of patterned coatings, i.e., stripes of different orientation and droplet patterns. We investigate the transitions between the different patterns as triggered by changes in the control parameters inherent to slot-die coating, e.g., the liquid viscosity and the coating gap height. The relatively simple theoretical approach is based on lubrication theory. It is already able to repro- duce most of the patterns observed experimentally, and reveals a wettability-driven instability mechanism.

Details about the publication

JournalPhysics of Fluids
Volume35
Issue7
Page range074117null
StatusPublished
Release year2023
Language in which the publication is writtenEnglish
DOI10.1063/5.0150340
KeywordsThin film deposition; Thin films; Self assembly; Liquid solid interfaces; Interfacial tension; Fluid mechanics; Newtonian fluids; Lubrication flows

Authors from the University of Münster

Hartmann, Simon
Professur für Theoretische Physik (Prof. Thiele)
Thiele, Uwe
Professur für Theoretische Physik (Prof. Thiele)