Dish-like drying patterns of the water-soluble gelatin sheet wetted by an aqueous droplet

• “Dish”-like structures formed simply by drying a gelatin sheet wetted by water droplet at room temperature and humidity.
• Arrayed ring clusters of “dishes” forms at the broad ring area and further grow outward toward multiple-arrays with time.
• The patterns form by the cooperation of wetting, swelling, dissolving, evaporative, convectional, sedimentary and solidifying processes.

Drying dissipative patterns of the water-soluble gelatin sheet wetted by an aqueous droplet were observed as a function of time elapsed. The arrayed clusters of dishes formed at the broad ring area and grew outward toward multiple arrays with time. The drying patterns formed by the cooperative contribution of wetting, swelling, dissolving, evaporative, convectional, sedimentary and solidifying processes. Drying patterns were studied also for aqueous ethanol, aqueous NaCl solutions and dispersions of colloidal silica and poly(methyl methacrylate) spheres. The dish patterns were observed for the water-soluble substrates, for the first time, in this work.

Figure optionsDownload as PowerPoint slideTypical patterns during drying processes of a gelatin sheet wetted with a water droplet at 26 °C. 0.3 ml, (a) 3 min after setting, (b) 20, (c) 50, (d) 21 h15 min (dry), frame size: 24.8 mm × 24.8 mm.