PESPECTROPHOTOMETRY OF DYNAMIC COLOURS (PO42, Pages 408-416)

Dynamic colours are sensitive on different stimuli such as UV-VIS radiation, temperature, humidity, etc. Potential application of these systems in industry, fashion and other branches brings problem of its measurement for purpose of control their quality. For example photochromic colours need to be exposed by external light source during measurement. Based on that the special device was developed allowing such kind of measurement. This unique device allows the measure colorimetric and spectral characteristics of colour changeable materials as photochromic sensors and also the fatigue test for the control of colour change stability. This measurement of colorimetric and spectral parameters in comparison together with intensity of UV irradiation allows finding the dependence of colour change on intensity of irradiation and the development the scale for individual visual observation and to evaluate dangerousness of UV irradiation. In this article is described possibility to use different light sources (Xe 450 W and LED 395-410) for this kind of measurement and also there influence of selected light sources on photochromic effect is discussed. Is evident, there is a problem for future standardization of colour changeable materials measurement.