Funded by DARPA and the National Science Foundation, a new nano-scale production process allows researchers at the University of Michigan and in South Korea to develop plastic films that when breathed upon reveal hidden images.
Traditional anti-counterfeiting measures such as holographic displays and paper-based watermarks are easily replicated. In response, researchers were motivated to develop nano-scale markers that make counterfeiting them nearly impossible. Nicholas Kotov, the Joseph B. and Florence V. Cejka Professor of Chemical Engineering, says, “One challenge in fighting counterfeiting is the need to stay ahead of the counterfeiters.”
The method involves producing plastic molds dotted with hundreds of nanopillars “500 times smaller than the width of a human hair.” Next, a special blend of polyurethane and adhesive is used to cover the mold that when cured, slightly shrinks and pulls away (with the nanopillars embedded within) from the mold, making the material stronger, resistant to rubbing, and able to stick to a variety of surfaces like plastics, paper, fabrics and metal.
Finally, these sheets are then fed through a nano-scale printer that applies tiny drops to fill-in the spaces that exist between the pillars where the images are meant to appear. When breathed upon, the moisture from our breath clings to the surrounding pillars to reveal the filled-in image.
The latest security features, while appealing and cutting edge, are often expensive to implement on a large scale. Fortunately, this new nano-scale watermark process is surprisingly cheap, which can be produced at US$1 per square inch. As a result, the University of Michigan is seeking patent protection for their production process and are actively looking for a commercial partner to help them bring this material to market. As cool as this is, it’ll be an amusing experience when you walk into a store and see people breathing on a variety of products and items for authentication. And I’m not quite sure I’d want every cashier breathing on my credit cards. Hmm…