Whiter than white: beetles have us beat
Nature has inspired many technologies and material developments, like the beetle that inspired anti-theft technology or the whale that inspired fan blades. Now, another beetle is inspiring researchers to look at new ways to make white.
White is everywhere around us: on walls, cars, paper, clothes and plastic bags, but in nature it’s actually pretty rare, reports the BBC. The beetle in question, Cyphocilus, is one of those rare cases – it blends in with certain white mushrooms in South East Asia.
For those of you who are very close readers of TreeHugger, you may notice that we’ve written about this before – in 2007, in fact. At the time scientists were impressed by how brilliantly white the Cyphocilus beetle was, and how efficiently it scattered light to make white. But back then, the mechanism wasn’t fully understood.
What they found out since then further surprised them – the beetles’ scales were made up of disordered chitin fibres which could reflect white in a much thinner layer than any paint or paper.
“If one were to make paper of the same thickness, it would be translucent,” one of the researchers, Ullrich Steiner, told TreeHugger.
We’re taught from a young age that the white is the presence of all colours, but the science behind it is more complicated. To form white, all colours must deflect equally and bounce within a material multiple times in a randomized manner - not easy to make.
There are multiple ways of producing white. Paint, for example, is made of nanoparticles of titanium dioxide. Generally, there need to be many layers of nanoparticles to form the desired white. That’s why the Cyphocilus beetles’ thin layer is so impressive. It’s also why the beetles’ mechanism could have important application at the industrial level.
"‘White’ is a rather wasteful color,” added Steiner. “Paper, for example has to be about a tenth of a millimeter thick to be properly white and not translucent. This translates into reasonably large amount of material that is required to make, say, a page of paper. For an insect that needs to fly, this corresponds to a rather large weight it has to carry.”
With more studies, scientists could theoretically develop a more environmentally friendly white that is potentially more cost effective.
“Using way less material, and a more environmental friendly one, [such] as those biopolymers like cellulose and chitin [which] are of course renewable, abundant (they are by far the most common biopolymers of the planet), biocompatible, and even edible, if you feel like!” Researchers Lorenzo Pattelli and Lorenzo Cortese wrote us in an email.
While it sounds like a great plan, Steiner reminds us that paper and white paint are already very cheap to produce, so it would be hard to compete with current industrial methods. But that doesn’t mean that more research can’t be done.
“Hopefully this new knowledge will let us create new products with same to superior “performance” in terms of appearance using less raw material, which is of course desirable in many applications under both the economical and the environmental point of view,” added Pattelli and Cortese.