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Nanotech Cash to Outwit Counterfeiters

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Nanotech Cash to Outwit Counterfeiters

(Professor Charles Duke, Physics & Astronomy)

by Lois. H. Gresh

February 27, 2007: Professor Charles Duke of the University of Rochester Physics Department noted today that a committee of experts is suggesting that in the not-so-distant future, a dollar may become more than a printed piece of paper: it may be a nanotechnology machine that outwits counterfeiters. In a groundbreaking study, A Path to the Next Generation of U.S. Banknotes: Keeping Them Real, commissioned by the U.S. Bureau of Engraving and Printing (BEP) and produced by the National Research Council (NRC), Duke and other members of the NRC Committee on Technologies to Deter Currency Counterfeiting, suggest 16 high-tech changes to America's cash. Among them are embedded magnifying lenses, materials that create holograms, temperature-sensitive inks, high-pressure printing, and most remarkable, molecules inside the bills that continually change how they feel and what they look like.

As counterfeiting technology moves full swing into the twenty-first century, mechanisms must be in place to secure our twenty-first century cash. It may no longer suffice to use our current counterfeit detection methods: visual scanning of colors and patterns, for example.

The science and engineering experts on the NRC Committee offer solutions that range from near-term (the next seven years) to more long-term measures. Specific examples include:

• Digitally encrypt the bill

• Add a tiny magnifying lens to the bill, so when the bill is folded, someone can use the lens to view
  embedded micro-images that guarantee the bill's authenticity

• Use ink that changes color based on temperature

• Use ink that changes color in different wavelengths of illumination

• Add a transmitted light image, such as a transparent registration component, that
  cannot be reproduced readily by a copier

• Add fibers that scatter light in a unique way

• Add molecules that revise surface texture and feel

• Add a complex spatial pattern, such as a starburst, that electronic printers cannot reproduce

• Add chemical sensors, superelastic responsive materials, and tactilely active
  electronic features to the bill

• Use nanocrystal pigments to control absorption, scattering, and fluorescent signatures

• Nanoprint text, images, and regular arrays of patterns with critical dimensions in the submicron range.

While such changes won't come overnight, some of them will come within a decade or so. It will be interesting to see -- and feel -- the new $5 bill printed by the U.S. Treasury in 2008. Perhaps Abe Lincoln will smile and tip his hat.

Additional Details

For further details, see:

A Path to the Next Generation of U.S. Banknotes: Keeping Them Real, Committee on Technologies to Deter Currency Counterfeiting, National Research Council (The National Academies Press, February 26, 2007). Available for free download at: http://books.nap.edu/catalog/11874.html.

For more information, please contact:
   Professor Charles Duke
   Email: aed22cbd@frontiernet.net
   Faculty Webpage: http://spider.pas.rochester.edu/mainFrame/people/pages/Duke_Charles_B.html

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