NANOSECOND PULSED LASER CLEANING OF BURIAL CRUSTS FROM ANCIENT PERUVIAN COTTON TEXTILES: AN INITIAL INVESTIGATION INTO THE OPTIMUM PARAMETERS WITH PHOTOACOUSTIC ASSESSMENT

ALDAMA-REYNA C.W.; Fernández A.; AGREDA-DELGADO J.F.; VALVERDE-ALVA M.A.; Ocharán G.; Prieto G. · International Journal of Conservation Science (2026) · DOI: 10.36868/ijcs.2026.03.04

Resumen

This study evaluated the effectiveness of the pulsed photoacoustic technique in determining optimal laser fluence values for the laser cleaning of an ancient Peruvian archaeological textile. Scanning electron microscopy (SEM), diffuse reflectance spectroscopy, and atomic composition analysis confirmed the removal of dust and dirt layers adhered to the textile surface. Nanosecond-pulsed laser radiation at 532 nm and 1064 nm was directed onto the surface of the archaeological textile. During laser cleaning, the textile was manually displaced using a bidimensional micrometric translation stage. The photoacoustic technique allowed for the determination of the laser ablation threshold for dust and two distinct layers of adhered dirt. Laser cleaning at 532 nm with a fluence of 300 mJ/cm² was found to be optimal; however, it was not effective in removing salt deposits adhered to the textile surface. The effectiveness of laser cleaning was compared with conventional methods such as mechanical and wet cleaning. The results demonstrated that the 532 nm laser cleaning method successfully produced a clean archaeological textile without yellowing or morphological modifications to the cotton fibers.

Instituciones: Universidad Nacional de Trujillo