Thermochromic ink as a smart indicator on cold product packaging - review

Good product packaging is one of the fundamental determinants of the quality of a product. Packaging can protect a product, but it can also be used as an indicator so that consumers know the quality level and shelf life of the packaged products. Along with the development of modern packaging science and technology, it is developing into intelligent packaging that is directly linked to Consumers about the quality and quality of the packaged products without opening the packaging. One of the smart packaging trends that have been developed is thermochromic ink which can be applied in the form of foils or packaging labels. Thermochromic ink is already well developed and applied to textiles and smart windows. Thermochromic ink development on the packaging is used for printing packaging labels and foils placed on the surface of the package. Thermochromic ink changes colour when there is a change in processing and storage temperatures. The ink used is an oil-based synthetic ink with ethanol and water as solvents. The particle size of the thermochromic ink is quite large, and it is quite difficult to obtain a stable colour, so the thermochromic ink must be microencapsulated to protect it from the environment.