Photochromic Print's Distinct Photo-Fading Characteristics under Continuous UV Irradiation Measurement Modes

Abstract When studying photochromic materials, photostability and endurance are crucial considerations. These characteristics can benefit UV sensors, optical rewritable storage devices, and anti-counterfeiting techniques, as well as the ophthalmic industry. When light irradiates a photochromic system, chromophoric dye molecules, the chromophoric part of the dye, and fatigue resistance refer to how well they hold up against photodegradation, photobleaching, and photooxidation. In our experiment, we examined the photo-fading tendency of a photochromic dye with photochromic textiles. We used the screen-printing technique to create photochromic prints with different dye concentrations. We then continuously exposed the prints to UV light using a spectrophotometer. UV light caused the photochromic dye molecules in these prints to fade and photodegrade. We used three distinct ways to assess UV irradiation over many cycles. We proposed three hypotheses: When photodegraded using various techniques, the UV dosage exhibits additive behaviour during recorded UV irradiance cycles. In addition, a visible light source is more likely to cause photodegradation entirely or partially when the reversion process repeats over several cycles. Next, the prints exhibit photofading when subjected to one UV cycle and multiple irradiance cycles within a single measurement block and numerous irradiance cycles within a single measurement period. The plateau of each measured photochromic cycle adheres to the one-phase dissociation feature for photo-fading behaviour. In contrast, the colour span values for the photochromic system, measured during the development phase of each UV irradiation cycle, fit the one-phase association model.