Description of photochromic textile properties in selected color spaces

Abstract

Research in color science includes studies on the spectral properties of light and the perception of color by the human eye and the brain. Color spaces allow the description of the position of a color by using three basic attributes, namely lightness, chroma and hue. Photochromic pigments used as a component of ultraviolet sensors can help to define color changes in time through the measurement of color differences in exposition and decay phases. The change of color can be evaluated in terms of the light source employed, reversion and the kinetics of photochromic effects. Commercial spectrometers are not suitable for this type of measurement. These instruments cannot measure the kinetics of exposure and the decay phase of photochromic materials. A unique spectrophotometer and a methodology for measuring colorimetric and spectral data of photochromic pigments in selected color spaces are presented. This work is the first step towards standardization of the measurement of color-changing materials containing functional dyestuffs, such as photochromic pigments.