# Self-organised dip-coating patterns of simple, partially wetting, nonvolatile liquids

## TL;DR

This paper predicts a new self-organized pattern formation regime in dip-coating of simple, partially wetting, nonvolatile liquids, driven by a meniscus instability from competing dewetting and film deposition.

## Contribution

It introduces a third coating regime characterized by regular liquid ridge patterns, supported by combined analytical and numerical analysis of the hydrodynamic thin-film model.

## Key findings

- Existence of a pattern deposition regime in dip-coating.
- Pattern formation driven by meniscus instability.
- Mechanism involves competition between dewetting and Landau-Levich film deposition.

## Abstract

When a solid substrate is withdrawn from a bath of simple, partially wetting, nonvolatile liquid, one typically distinguishes two regimes, namely, after withdrawal the substrate is macroscopically dry or homogeneously coated by a liquid film. In the latter case, the coating is called a Landau-Levich film. Its thickness depends on the angle and velocity of substrate withdrawal. We predict by means of a numerical and analytical investigation of a hydrodynamic thin-film model the existence of a third regime. It consists of the deposition of a regular pattern of liquid ridges oriented parallel to the meniscus. We establish that the mechanism of the underlying meniscus instability originates from competing film dewetting and Landau-Levich film deposition. Our analysis combines a marginal stability analysis, numerical time simulations and a numerical bifurcation study via path-continuation.