Effects of ionizing radiation on the color and morphology properties of leather

Abstract

Effective conservation strategies for leather artifacts and art objects are essential for preserving cultural heritage, particularly given the inherent vulnerability of the material to biodegradation, as leather, an organic material, is especially susceptible to this process. Gamma radiation has emerged as a promising method for the disinfestation and disinfection of cultural heritage objects and archival materials. This study aimed to advance the understanding of gamma radiation as a conservation technique for vegetabletanned snake and chrome-tanned bovine leather, specifically focusing on its effects on chromaticity, surface topology, fiber structure and thermal behavior. Gamma radiation was applied at controlled doses of 1 and 3 kGy, and its impact on the morphology of the leather was assessed using colorimetry within the CIELAB color space and field emission gun scanning electron microscopy (FEGSEM). The findings indicated that gamma radiation at these doses induced minimal alterations in the morphological properties of the leather. The color differences for irradiated and non-irradiated samples were negligible, with total color differences (ΔE) remaining within acceptable limits (ΔE < 3). Moreover, FEGSEM analysis demonstrated that the fiber structure and surface morphology were not significantly compromised by the irradiation process. Thermogravimetric analyses showed similar thermal decomposition between nonirradiated and irradiated samples for both bovine and snake leather, with detailed data analysis indicating thermal stability. The results supported the efficiency of gamma radiation as a conservation technique for both bovine and snake leather artifacts, preserving their aesthetic and structural integrity.