2019/05/10 by Alban Sauret, Adrien Gans, Bénédicte Colnet +4 · 35 citations
Engineering · Materials Science · Physics and Astronomy · #Capillary action #Coating #Dip-coating #Entrainment (biomusicology) #Filtration (mathematics) #Fluid Dynamics and Thin Films #Impurity #Layer (electronics) #Micro and Nano Robotics #Pickering emulsions and particle stabilization #Resistive touchscreen #cond-mat.soft #physics.flu-dyn
paper · pdf · doi:10.1103/physrevfluids.4.054303
published in Physical Review Fluids 4(5) (American Physical Society)
openalex publication_date 2019/05/10 · openalex created_date 2019/05/16 · arxiv created 2020/11/27 · arxiv updated 2020/11/30 · openalex updated_date 2026/08/05
An object withdrawn from a liquid bath is coated with a thin layer of liquid. Along with the liquid, impurities such as particles present in the bath can be transferred to the withdrawn substrate. Entrained particles locally modify the thickness of the film, hence altering the quality and properties of the coating. In this study, we show that it is possible to entrain the liquid alone and avoid contamination of the substrate, at sufficiently low withdrawal velocity in diluted suspensions. Using a model system consisting of a plate exiting a liquid bath, we observe that particles can remain trapped in the meniscus which exerts a resistive capillary force to the entrainment. We characterize different entrainment regimes as the withdrawal velocity increases: from a pure liquid film, to a liquid film containing clusters of particles, and eventually individual particles. This capillary filtration is an effective barrier against the contamination of substrates withdrawn from a polluted bath and finds application against biocontamination.