Our Research

Responsive Materials for Security Applications

The project, directed at the counterfeit and fraud market, was funded to 2004 under the DTI-EPSRC LINK Management of Information programme under the title XVista. The Loughborough based part was jointly run by Dr R.J. Mortimer and Dr David R. Worrall with Dr Siân L. Williams Worrall as researcher. The work ran in parallel with work at the industrial partners (Wilson Process Systems Ltd) and at the School of Engineering, University of Sussex, where the electronic aspects of image encoding, sensing, systems processing and integration were investigated. Chemical species which respond to an external stimulus have great potential for application in a number of fields including safety, technical textiles, security labelling and counterfeit detection. For example, luminescent materials which emit visible light when excited with Ultra-Violet light find application in banknote security. However, materials which respond to external stimuli with large changes to their electronic or chemical structure open up much greater possibilities for exploitation. Such materials can be essentially invisible until exposed to an external stimulus such as light or an electric field, at which point they can be detected and information encoded therein read. Detection can be optical or capacitive; in either case, it is possible for the materials to remain invisible to the naked eye even in the readable state, by judicious choice of materials properties. In addition, switching between readable and non-readable states can, in many circumstances, be readily controlled. Hence such materials can be incorporated as an invisible identifier within an article, and can act as a powerful defence against the serious problem of brand counterfeiting.

Back to Photochemistry Group Home page