A team of researchers from the University of Hong Kong is aiming to improve the anti-counterfeiting measures designed to protect assorted products and, subsequently, the global economy and security.

In lieu of commonly used QR codes and other anti-counterfeiting measures, which can be easily produced thanks to limited data encryption capacity on a planar space, the researchers are attempting to increase encryption density in a limited space using a new 3D printing method.

3D printing process of polarization-encoded 3D micro-pixels. Source: The University of Hong Kong3D printing process of polarization-encoded 3D micro-pixels. Source: The University of Hong Kong

The new 3D printing method, according to its developers, produces polarization-encoded 3D anticounterfeiting labels that reportedly encrypt more digital data than 2D labels.

To accomplish this, the team used diphenylalanine (FF), which is a species of dipeptides chosen for data encryption applications thanks to its unique optical properties; specifically, piezoelectricity and optical birefringence, which are due to the material’s crystalline nature.

"Our new 3D printing method combined with nature-driven molecular self-assembly can print multi-segmented 3D FF micro-pixels with programmed crystallinity for high-density data encryption. By utilizing different responses of the amorphous and crystalline segments to polarized light, a tiny single 3D pixel can encrypt a multi-digit binary code consisting of '0' and '1.' The information capacity can be increased to 211 with a single eleventh-segmented freestanding pixel on a tiny 4 µm2 area which is 1,000 times smaller than a hair strand," the researchers explained.

The team suggests that the 3D printing technology could be used to create custom security labels — anywhere and anytime — thereby improving information security.

An article detailing the technology, "Three-Dimensional Printing of Dipeptides with Spatioselective Programming of Crystallinity for Multilevel Anticounterfeiting," appears in the journal Nano Letters.

To contact the author of this article, email mdonlon@globalspec.com