Wrinkled polymers have anti-counterfeit potential

Researchers in Korea have developed a polymer-based taggant that can be used to authenticate products and is claimed to be impossible to copy.

The team from Seoul University describe in the journal Advanced Materials a system based on silica-coated polymers that when dried form a distinctive and unique wrinkle pattern, mimicking the nature of human fingerprints.

The tags are technically unclonable because - even if the process to make them were reproduced exactly - no two are alike, say the scientists, who have generated a library of unique taggants that can be added to a broad range of products and detected using various optical decoding methods.

The level of complexity of the wrinkling pattern -and thus the security of the tag - could be changed and controlled by altering the production process, for example by using different reaction times and changing the amount of ultraviolet light used to create the polymers.

While other taggants claim to be unreplicable they have often "lacked sufficient intelligent code control mechanisms as well as practical applicability for a wide range of products," write the authors, led by Wook Park and Sunghoon Kwon.

"Previous PUF [physical unclonable function] taggants are not sufficiently adaptable for an industry-suitable authentication strategy," they continue.