INST Develops Anti-Counterfeit Luminescent Ink with Rare Earth Nanomaterials

A new security ink with luminescent properties and unique colour-changing capabilities under various light wavelengths promises enhanced counterfeit protection for currency, certificates, medicines, and branded goods.

Counterfeiting remains a critical challenge worldwide, with counterfeit currency, certificates, branded goods, and pharmaceuticals posing significant economic and health risks. In response, researchers at the Institute of Nano Science and Technology (INST), under the Department of Science and Technology, have developed an innovative luminescent nanomaterial-based ink. This security ink employs rare earth ions with unique luminescent properties, enhanced by bismuth, to combat the duplication of items requiring secure verification.

Advanced Luminescent Features for Stronger Anti-Counterfeit Protection

This ink offers superior security features by displaying distinctive colors under different wavelengths of light. Unlike traditional security inks, which are typically only visible under UV light and easily replicable, INST’s ink exhibits diverse colors under UV and near-infrared (NIR) light. Specifically, the ink appears as:

Vibrant blue under 365 nm UV light

Pink under 395 nm light

Orange-red under 980 nm NIR light

These color variations enhance the ink’s uniqueness, making it difficult for counterfeiters to replicate. Additionally, the ink is stable across a range of light, temperature, and humidity conditions, making it a versatile solution for a variety of products and climates.

Innovative Synthesis and Application Process

The luminescent nanomaterial was synthesized using a co-precipitation method at 120°C and subsequently dispersed into commercially available PVC ink through sonication, a process that disperses nanoparticles into solvent by applying sound energy. Once integrated, the ink was applied to various patterns and letters through a screen-printing technique, showing consistent and distinct colour shifts when exposed to different wavelengths, validating its security effectiveness.

Applications in High-Security Products

By incorporating rare earth ions and bismuth, known for their characteristic emissions, INST scientists have enhanced the encryption and decryption capacities of the ink, improving its security features. This luminescent ink is adaptable for high-security applications, allowing for counterfeit detection across multiple sectors:

Currency and certificates: Protects against forged documentation and currency duplication.

Medicines: Ensures product authenticity in the pharmaceutical industry, where counterfeits can endanger health.

Branded goods: Helps manufacturers prevent the sale of counterfeit versions of their products, safeguarding brand integrity.

This development marks a significant advancement in anti-counterfeiting technology, providing both manufacturers and consumers with an efficient, user-friendly tool to detect and verify authenticity and quality.