Smart packaging by the application of sensitive dyes

Abstract

Smart packages can communicate with their users or other clients via the Internet of Things. By means of sensitive dyes implemented in an intelligent code, the code is able to report the history of critical environmental influences on the package and accordingly on the packed goods during the entire transport path. So all steps from manufacturing to delivery can be traced without any energy supply. Moreover, these intelligent codes are composed of different sensitive dyes in the form of dots. Each smart dot can change its colour from an inactive state into active states, in the form of colour gradations. Thus, a critical value of colour gradation can be defined as limitations that set the sensitive dot’s state from inactive [0] to active [1]. Hence, static consumer or product information and dynamic information about environmental influences – e.g. water/moisture, temperature, UV-light, pressure, acids, etc., can be stored in one entire code. The use of various sensitive dyes also adds a significant anti-counterfeiting feature and a chemical fingerprint. The intelligent code can be cost-efficiently printed as a printable sensor. Furthermore, the intelligent code can be read and analysed by usual smart devices, e.g. smartphone, tablet, etc. – linked to a specific web server where the code can be compared with its original state, to indicate critical deviations. The foreground of this paper is the application of sensitive dyes (sensitive dyes are as well named as smart materials) in order to get information for comprehensive research. First, the printability of the sensitive dyes is examined as well as their reaction process and behaviour depending on technical parameters, e.g. viscosity. Second, their reaction processes and reaction times in dependence on different layer thicknesses based on various polyester screens and the remissions of the printed samples are analysed. Third, the characteristic wavelength changing of the sensitive dyes is shown, which will allow further investigations by a smartphone.