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Updated: Dec 25, 2025
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Patterning of Microorganisms and Microparticles through Sequential Capillarity-assisted Assembly
Published on: November 4, 2021
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Patterning of colloids into spirals via confined drying.
Ranajit Mondal1, Madivala G Basavaraj1
1Polymer Engineering and Colloid Science Laboratory (PECS Lab), Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai-600036, India. basa@iitm.ac.in.
Soft Matter
|April 3, 2020
Summary
Drying colloidal dispersions in parallel plates creates unique spiral patterns. This self-assembly is driven by continuous stick-slip motion of the drying contact line.
Area of Science:
- Complex fluid dynamics
- Colloid science
- Materials self-assembly
Background:
- Drying of complex fluids is crucial for forensic science, lithography, printing, and coating.
- Understanding particle deposition during drying is key to controlling material properties.
Purpose of the Study:
- To investigate self-assembly patterns in charge-stabilized colloidal dispersions dried under parallel plate confinement.
- To elucidate the role of contact line dynamics in pattern formation.
Main Methods:
- Drying colloidal dispersions between two parallel plates.
- Analyzing the three-phase contact line dynamics during solvent evaporation.
- Observing particle deposition patterns.
Main Results:
- Colloidal dispersions dried in parallel plate confinement form spiral deposition patterns.
- Pattern formation is independent of confinement spacing and particle shape.
- Continuous stick-slip motion of the contact line, propagating locally, drives spiral formation.
- The number of spiral turns is influenced by dispersion volume and particle concentration.
Conclusions:
- Parallel plate drying offers a novel route to self-assembled colloidal structures.
- Contact line dynamics are critical in dictating the morphology of dried colloidal deposits.
- The findings have implications for developing advanced printing and coating technologies.
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