Date of Publication :7th December 2023

Abstract: In various practical contexts, printed images or textual content are subjected to light exposure, rendering their lightfastness a critical parameter. Adequate lightfastness ensures consistent color stability even with extended usage. This work aims to characterize the color-fading behavior in electrophotographic prints under the influence of light source exposure The application of electrophotography prints has witnessed a notable surge in recent times, expanding its scope beyond conventional document printing to art and photography. There is an increasing concern about the longevity and color stability of electrophotographic print. In this study, the Altona test color chart has been printed using the electrophotographic method on the paper substrate and has been exposed to an accelerated aging procedure utilizing a xenon arc lamp to examine the deterioration of color. The test chart that has been printed consisted of six solid color patches (red, green, blue, cyan, magenta, and yellow). The spectrophotometric measurements of the prints have been performed using a Spectroradiometer, and the data has been analyzed using Principles Component Analysis (PCA). The color fading observed in all the color prints adheres to the characteristics of type II fading. This fading pattern is characterized by an exponential and rapid color shift within the initial 10 hours of exposure, followed by a gradual and linear decline. To analyze the rate at which color fading occurs, a curve fitting method was employed, utilizing a first-order kinetic model. The level of fit quality, represented by R², is approximately 0.95 across all color patches. The fading behavior of the colors results from a combination of distinct kinetics, yet the fading rate itself exhibits a singular nature. The study has shown that each color patch has exhibited a unique level of light sensitivity, influenced by factors such as toner composition, substrate material, fusion temperature, and the light source employed.

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