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Updated: Apr 27, 2026
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Film Control to Study Contributions of Waves to Droplet Impact Dynamics on Thin Flowing Liquid Films
Published on: August 18, 2018
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Control over coffee-ring formation in evaporating liquid drops containing ellipsoids.
Venkateshwar Rao Dugyala1, Madivala G Basavaraj
1Polymer Engineering and Colloid Science Lab (PECS Lab), Department of Chemical Engineering, Indian Institute of Technology-Madras , Chennai 600 036, India.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 9, 2014
Summary
Controlling deposit patterns from evaporating droplets is key for materials engineering. This study shows that tuning particle interactions, not particle shape, dictates whether a ring or uniform film forms.
Area of Science:
- Materials Science
- Physical Chemistry
- Fluid Dynamics
Background:
- Evaporation-driven pattern formation in sessile drops has broad applications.
- Controlling these patterns is crucial for advanced material fabrication.
Purpose of the Study:
- To experimentally investigate how particle shape and Derjaguin-Landau-Verwey-Overbeek (DLVO) interactions influence deposit patterns.
- To determine the key factors controlling pattern formation in evaporating sessile drops.
Main Methods:
- Utilized a model system with monodisperse particles, allowing adjustment of aspect ratio and surface charge.
- Varied particle-particle and particle-substrate interactions to observe effects on deposit patterns.
Main Results:
- Coffee-ring formation occurred when particle-particle repulsion exceeded particle-substrate attraction.
- Uniform films formed when both particle-substrate and particle-particle interactions were attractive.
- For hydrophilic submicron ellipsoids, deposit patterns depended on interaction types, not particle shape.
Conclusions:
- Particle interactions are the primary determinant of deposit patterns in evaporating sessile drops.
- Tailoring DLVO interactions offers a method to control pattern formation for applications in materials engineering and beyond.
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