Controlling droplet spreading with topography

  title={Controlling droplet spreading with topography},
  author={Pallav Kant and Andrew L. Hazel and Mark Dowling and Alice B. Thompson and Anne Juel},
We present a novel experimental system that can be used to study the dynamics of picoliter droplet spreading over substrates with topographic variations. We concentrate on spreading of a droplet within a recessed stadium-shaped pixel, with applications to the manufacture of POLED displays, and find that the sloping side wall of the pixel can either locally enhance or hinder spreading depending on whether the topography gradient ahead of the contact line is positive or negative. Locally enhanced… 

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