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Updated: May 25, 2026
09:23
Reactive Inkjet Printing and Propulsion Analysis of Silk-based Self-propelled Micro-stirrers
Published on: April 26, 2019
Hydrodynamics of writing with ink
Jungchul Kim1, Myoung-Woon Moon, Kwang-Ryeol Lee
1School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-744, Korea.
Physical Review Letters
|January 17, 2012
Summary
We developed a minimal theory and experiments to understand how ink lines form on paper. Our model accurately predicts linewidth based on capillary forces and substrate resistance, explaining ink spreading dynamics.
Area of Science:
- Fluid dynamics
- Materials science
- Surface science
Background:
- Ink-based writing relies on liquid transfer from a pen to porous paper.
- The final ink linewidth is influenced by writing speed and material properties.
Purpose of the Study:
- To quantify the dynamics of ink spreading during writing.
- To develop a predictive model for ink line formation.
Main Methods:
- Experimental analysis using a simplified pen and a model paper surface (micropillar array).
- Theoretical modeling balancing capillary forces and substrate resistance for liquid flow.
Main Results:
- The study quantifies the relationship between pen speed, ink properties, and paper characteristics in determining linewidth.
- The developed theory successfully predicts the ink front shape and final line width.
Conclusions:
- A minimal theoretical framework explains ink line formation dynamics.
- Experimental validation confirms the predictive power of the model for capillary-driven ink spreading.
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