Removal of overpaintings from easel paintings using LQS Nd:YAG laser

• Published in: Applied physics. A, Materials science & processing Vol. 117; no. 1; pp. 341 - 346
• Main Authors: Ciofini, D., Osticioli, I., Pavia, A., Siano, S.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-10-2014
• Subjects: Characterization and Evaluation of Materials; Condensed Matter Physics; Machines; Manufacturing; Nanotechnology; Optical and Electronic Materials; Physics; Physics and Astronomy; Processes; Surfaces and Interfaces; Thin Films; Chrome Yellow; Optical Penetration Depth; Laser Damage Threshold; Paint Layer; Thermal Diffusion Length
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-014-8318-2

The removal of overpaintings from valuable easel paintings represents a very difficult challenge, which is traditionally approached using solvents and moderate mechanical actions. Here, we explore for the first time the potential of Long Q-Switching Nd:YAG (1,064 nm) laser with a pulse duration of 120 ns for selective ablation of overpainting layers. Mock-ups were prepared in order to approach in a systematic way a concrete uncovering problem concerning a modern painting on canvas. The former were prepared according to the stratigraphy and material compositions of the latter, as measured using optical and ESEM-EDX microscopy along with infrared and portable Raman spectroscopy. The parameterization achieved on the mock-ups allowed interpreting and maximizing the selectivity of the laser conservation treatment carried out on the real case.