Butterfly wings used to print self-cleaning windows

ANY child can make a butterfly print, but doing so on an industrial scale is far from child’s play.

Butterfly wings – and lotus leaves – are able to repel water with ease because of the microstructures on their surface. The densely packed microscopic bumps of the lotus leaf and the waffle-like structures found on butterfly wings both make it difficult for water droplets to spread out. As a result, the drops roll off, and they take dirt with them. This makes…