3D printable phase change information storage label films for dynamic and multi-level anti-counterfeiting.

Anti-counterfeiting technology demands continuous innovation to address escalating global counterfeiting challenges. This study introduces 3D printable phase change information storage label films for dynamic, multi-level anti-counterfeiting applications. Utilizing extrusion-based 3D printing, customizable anti-counterfeiting labels with complex encrypted information such as barcodes and QR codes were fabricated. These labels leverage the thermal responsiveness of phase change materials (PCMs) to reveal hidden information under infrared thermography at specific temperature and specific duration, while remaining concealed at ambient or elevated temperatures. Notably, a multi-level encryption strategy is achieved by integrating PCMs with distinct phase transition temperatures (30 °C and 53 °C), enabling sequential decryption of information at different temperature intervals. This approach significantly enhances anti-counterfeiting complexity and security. The work demonstrates the potential of PCM-based 3D printing for high-capacity information storage and adaptable anti-counterfeiting solutions, offering a versatile platform for diverse industrial applications.