This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
In 1966, five guys with a bunch of regular office supply store paper created hundreds of thousands of dollars in counterfeit $10 Australian bills. This, just weeks after Australia had introduced a new series of banknotes — what they had touted as their most advanced, most secure yet.
The Royal Bank of Australia, stumped, made the decision to turn to scientists. Meetings were held. The Globe and Mail reported that a crucial moment during one, attended by a young chemist named David Solomon, went like this:
Why don’t we use polymer?” Mr. Solomon said, using what he calls “a fancy word for plastic.”The room fell silent, Mr. Solomon, now 81, recalls. Some people laughed. Plastic money?
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The plastic substrate could be embossed, could support optically variable devices (images that change when viewed at different angles), and importantly, was not available at Staples. After twenty years of collaboration between the Reserve Bank of Australia and the Commonwealth Scientific and Industrial Research organization, the first polymer bank note was issued in 1968, appropriately, in the denomination of $10. By 1996, all Australian banknotes were made of plastic.
Thirty-some countries now use polymer banknotes. If you’ve headed North recently, you might have noticed that Canada is among the most recent. Reportedly sparked by a spike in counterfeiting at the beginning of the millennium, the Bank of Canada spent $20 million in R&D (and about fifteen times that in total production costs), and produced 15 million test notes to create their new polymer series which are printed on the same biaxial-oriented polypropylene substrate that was produced by Australia for their 1998 banknote. Bills in denominations of $20, $50, and $100 were introduced in 2012, with $5 bills and $10 planned for release by the end of 2013.
The bills, which the Bank of Canada claims are the most secure in the world, feature raised ink, a large transparent window, and a frosted maple leaf that contains hidden numbers visible when the note is held up to the light.They also are the first to feature holographic foil — the shiny stuff that is printed on part of the clear window.
They were subjected to a battery of physical tests as well, subjected to fake sweat, extreme temperatures, and crumpling. (In the video below you can also see a scientist spreading jam on a bank note and wiping it off.)
The plastic substrate not only allows the bill to last 2.5 times longer than traditional paper bills, but when it is done serving its time as a banknote it can be recycled. Bank of Canada Senior Analyst Julie Girard suggested “a lawn chair some day whose parts are made of currency,” to the BBC.
Not everyone is convinced that plastic banknotes are as durable as science says they are. One man claimed to the Toronto Star that a wad of $100s crumpled in his wallet when he placed it on top of a toaster oven; other rumors say that the notes melt into very expensive puddles). But the plastic can withstand temperatures between -103 and 284 degrees Farenheit — so theoretically you yourself would toast before the money did. (They are not, of course, totally indestructible: Snopes.com claims that a man in Syndney stashed $15,000 in the oven “only to have his wife (who ‘never used it’) turned it on to heat up fishsticks for the kids.”)
The US’s money is currently made of cotton and linen — albeit somewhat tricked out cotton and linen, with color-shifting ink, water-marks, and UV threads. Though not likely to change anytime soon — a polymer banknote collector mused to the MIT Technology Review that the US wants to be “convinced beyond a doubt that” that there is no problem with plastic money first — flashier security elements are being included: a $100 bill that includes a strip of polymer micro-lenses is currently in production.
It looks like it just might be our most secure currency yet.
