Serendipity: Hitting on the right note
Simon Singh is an author, journalist and TV producer, specialising in science and Mathematics. His latest book is "Trick or Treatment? Alternative Medicine on Trial", co-authored with Edzard Ernst, the world’s first professor of complementary medicine.
Sunday 07 March 1999
During the sermon that followed, he sat in his pew wondering if there was a way to make a more efficient bookmark. "I don't know if it was a dull sermon or divine inspiration," recalls Fry, "but my mind began to wander and suddenly I thought of an adhesive that had been discovered several years earlier by another 3M scientist, Dr Spencer Silver."
Silver had been trying to develop a new type of strong glue, but all his attempts ended in failure, since he only managed to create something that was slightly sticky.
Luckily, slightly sticky was exactly what Fry needed to create his sticky bookmark, now known as the Post-it Note. Silver's concoction was strong enough to support the weight of a piece of paper, yet weak enough not to tear the paper fibres when the note was removed.
Fry worked on the idea for the next three years, exploiting 3M's "15 per cent policy", which allows researchers to spend 15 per cent of their time doing whatever they like. Today there are over 400 Post-it Note products, including virtual Post-its for computer screens.
The science of stickiness is one of the most challenging areas of modern research, and it was only this year that researchers uncovered a new explanation for the sticking power of materials such as Post-it glue. The standard theory for predicting the force required to remove an object from a sticky surface assumes that all the stickiness is caused by the attraction between the glue molecules and the molecules of the object. This theory turns out to be inadequate, because it implies that the stickiness should be 10,000 times weaker than it actually is.
Recently, French physicists Cyprien Gay and Ludwik Leibler calculated the effect of an added factor, namely the millions of tiny bubbles at the interface between the sticky glue and whatever it is stuck to. Each bubble is roughly one thousandth of a millimetre in diameter, and each one acts as a miniature suction cup. When we attempt to pull an object away from a sticky surface, the bubbles are reluctant to expand, and they resist the pull. Gay and Leibler's idea seems to make sense, but it still has to be tested, so right now experimenters are filling their labs with sticky stuff in an attempt to measure the effect of the bubbles.
Simon Singh is the author of `Fermat's Last Theorem' (Fourth Estate, pounds 6.99)
Arts & Ents blogs
- 1 Home Office says Nigerian asylum-seeker can’t be a lesbian as she’s got children
- 2 What happens to your body when you give up sugar?
- 3 Drugs Live cannabis trial: Hash is less harmful than any other drug, expert claims
- 4 Turkish Airlines flight TK 726 crash-lands on Nepal runway amid dense fog
- 5 Apple and Google users being spied on for a decade because of 'Freak' security flaw
Durham Free School: 'Creationism taught at' free school facing closure
Nearly 100,000 of Britain's poorest children go hungry after parents' benefits are cut
Ukip would cut billions from Scottish budget to fund English tax cuts
End of the licence fee: BBC to back radical overhaul of how it is funded
Ukraine crisis: Top Chinese diplomat backs Putin and says West should 'abandon zero-sum mentality'
Boris Nemtsov shot dead: Outspoken Putin critic who had expressed fears for his life is killed near the Kremlin