A Novel Approach to Synthesise a Dual‐Mode Luminescent Composite Pigment for Uncloneable High‐Security Codes to Combat Counterfeiting

Abstract

A strategy is demonstrated to protect valuable items, such as currency, pharmaceuticals, important documents, etc. against counterfeiting, by marking them with luminescent security codes. These luminescent security codes were printed by employing luminescent ink formulated from a cost effective dual-mode luminescent composite pigment of Gd Yb Er O and Zn Mn S phosphors using commercially available PVC Gold medium. In the composite, Gd Yb Er O and Zn Mn S account for upconversion and downconversion processes, respectively. The synthesis procedure of the composite involves the admixing of Gd Yb Er O nanorods and Zn Mn S phosphor, synthesised by hydrothermal and facile solid-state reaction methods, respectively. The structural, morphological, microstructural, and photoluminescent features of Gd Yb Er O nanorods, Zn Mn S phosphor and composite were characterised by using XRD, SEM, TEM, and photoluminescence (PL) techniques, respectively. The distribution of PL intensity of the printed pattern was examined by using confocal PL mapping microscopy. The obtained results reveal that security codes printed using ink formulated from this bi-luminescent composite pigment provide dual-stage security against counterfeiting.

A facile synthesis of 1,3,6,8-pyrenesulfonic acid tetrasodium salt as a hydrosoluble fluorescent ink for anti-counterfeiting applications

“…Finally, the subnatant was treated with rotary evaporator at 60-80 C. The raw product was puried using saturated sodium chloride solution for recrystallizing to obtain the expected PTSA, as a yellow crystalline solid. 1…”

“…Anti-fake labels are extensively used in ID cards, bills, luxury items, and goods, and have become more and more important for public safety. 1 Traditional anti-counterfeiting technologies and materials are expensive, complex and can be easily copied. Hence, it is a signicant challenge to develop a kind of anticounterfeiting label that is cost-effective and hard to duplicate.…”

Super modules-based active QR codes for smart trackability and IoT: a responsive-banknotes case study

“…New smart labels able to real-time sensing and to establish H2H, H2M and M2M communication are a growing market busted by applications as Industry 4.0, Smart Cities, and Smart and Connected Communities 9 that is expected to worth 16.12 billion dollars by 2025 (https://www.grandviewresearch.com/industryanalysis/smart-label-market). In this framework, smart labels for authentication, trackability and counterfeiting detection, with controlled (public, restrict or encrypted) accesses to information are relevant [10][11][12] . From the user point of view, IoT smart labels should be reliable, ensuring the integrity, authenticity and preservation of information for objects in circulation or during transactions 13 .…”

Implanting bismuth in color-tunable emitting microspheres of (Y, Tb, Eu)BO3 to generate excitation-dependent and greatly enhanced luminescence for anti-counterfeiting applications

“…Recently, counterfeiting has grown to be a serious global threat, which includes the duplication of currencies, electronic products, merchandise, passports, official documents, pharmaceuticals, and so on [1]. Counterfeiting has caused enormous loss to the economy and a constant risk to the health and safety of consumers [1,2].…”

“…Recently, counterfeiting has grown to be a serious global threat, which includes the duplication of currencies, electronic products, merchandise, passports, official documents, pharmaceuticals, and so on [1]. Counterfeiting has caused enormous loss to the economy and a constant risk to the health and safety of consumers [1,2]. To prevent counterfeiting, a lot of advanced security technologies have been developed, including radio frequency identification, hologram attachment, isotope tracking and luminescent printing [3].…”