Polymer nanostructured material for the recording of biometric features

This communication describes the design, synthesis and application of a polymer multiphase nanostructured material as a recording medium. The material was produced from polymer multilayer particles containing three fluorescent dyes with largely non-overlapping absorption and emission spectra. Recording was conducted by selective photobleaching of the dyes localized in the different phases of the film. We demonstrate two distinct approaches to the recording of biometric features in the polymer material. In the first strategy, we encrypted in the polymer films full colour photographs with different shades of grey. In the second approach, we recorded three spatially overlapping biometric features in the same location of the material with no spectral overlap between them. Each feature was accessed by irradiating the material at a specific well-defined wavelength. The reported material can be used as a medium for the recording of biometric features of holders of identification documents.