24 Biomimetic Functions by Microscopic Molecular Reactions …
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Fig. 24.7 Comparison of bouncing phenomena of a water droplet (7.6 µL) on different surfaces.
Water-droplet-bouncing phenomena on a lotus leaf, and on diarylethene microcrystalline surfaces
with b single and c double roughness structure (h = 1.8 mm). Illustration of the parameters determining Laplace pressure (P L ) on d lotus leaf, and e single and f double roughness structures.
P L is determined by height H of surface structures and effective pitches p eff between almost
perpendicularly standing needles indicated by red color
a photoinduced crystal growth technique [19] by mixing two derivatives 1o and 3o
with expecting that two types of crystals grow on the surface with different sizes just
like the structure on termite wing. A solution containing equimolar amount of 1o and
3o was coated onto a glass plate. After the evaporation of the solvent in vacuo, the
surface of the microcrystalline was irradiated for 5 min with 313-nm light followed
by storage at 30 °C. This temperature is higher than both of the T g of 1o and 3o
crystals. Therefore, crystals of 1c and 3c grew on a softened surface above T g [8].
After storage of 9 days at this temperature in the dark, the surface was covered with
two types of needle-shaped crystals of 1c and 3c (Surf1c + 3c). SEM images at
415
Fig. 24.7 Comparison of bouncing phenomena of a water droplet (7.6 µL) on different surfaces.
Water-droplet-bouncing phenomena on a lotus leaf, and on diarylethene microcrystalline surfaces
with b single and c double roughness structure (h = 1.8 mm). Illustration of the parameters determining Laplace pressure (P L ) on d lotus leaf, and e single and f double roughness structures.
P L is determined by height H of surface structures and effective pitches p eff between almost
perpendicularly standing needles indicated by red color
a photoinduced crystal growth technique [19] by mixing two derivatives 1o and 3o
with expecting that two types of crystals grow on the surface with different sizes just
like the structure on termite wing. A solution containing equimolar amount of 1o and
3o was coated onto a glass plate. After the evaporation of the solvent in vacuo, the
surface of the microcrystalline was irradiated for 5 min with 313-nm light followed
by storage at 30 °C. This temperature is higher than both of the T g of 1o and 3o
crystals. Therefore, crystals of 1c and 3c grew on a softened surface above T g [8].
After storage of 9 days at this temperature in the dark, the surface was covered with
two types of needle-shaped crystals of 1c and 3c (Surf1c + 3c). SEM images at