Multianalytical non-invasive characterization of phthalocyanine acrylic
paints through spectroscopic and non-linear optical techniques
Authors: Dal Fovo A., Oujja M., Sanz M., Martínez-Hernández A., Cañamares M. V., Castillejo M., Fontana R.
Autors Affiliation: Consiglio Nazionale delle Ricerche – Istituto Nazionale di Ottica, CNR-INO, Largo Enrico Fermi 6, 50125 Firenze, Italy;
Università degli Studi di Firenze, Dip. Chimica, Via della Lastruccia 3, 50019 Sesto Fiorentino, Firenze, Italy; Instituto de Química Física Rocasolano, CSIC, Serrano 119, 28006 Madrid, Spain; Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid, Spain
Abstract: The documentation and monitoring of cleaning operations on paintings benefit from the identification and determination of thickness of the materials to be selectively removed. Since in artworks diagnosis the preservation of the object’s integrity is a priority, the application of non-invasive techniques is commonly preferred. In thiswork, we present the results obtainedwith a set of non-invasive optical techniques for the chemical and physical characterization of six copper-phthalocyanine (Cu-Pc) acrylic paints. Cu-Pc pigments have been extensively used by artists over the past century, thanks to their properties and low cost of manufacture. They can also be found in historical paintings in the form of overpaints/retouchings, providing evidence of recent conservation treatments. The optical behaviour and the chemical composition of Cu-Pc paintswere investigated through amulti-analytical approach involving micro-Raman spectroscopy, Fibre Optics Reflectance Spectroscopy (FORS) and Laser Induced Fluorescence (LIF), enabling the differentiation among pigments and highlighting discrepancies with the composition declared by the manufacturer. The applicability of Non Linear Optical Microscopy (NLOM) for the evaluation of paint layer thickness was assessed using the modality of Multi-photon Excitation Fluorescence (MPEF). Thickness values measured with MPEF were compared with those retrieved through Optical Coherence Tomography (OCT), showing significant consistency and paving the way for further non-linear stratigraphic investigations on painting materials.© 2018 Published by Elsevier B.V.
Journal/Review: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
Volume: 208 Pages from: 262 to: 270
KeyWords: Spectroscopic techniques; Non-invasive analysis; Phthalocyanine paints; Non-linear optical microscopy; Optical coherence tomographyDOI: 10.1016/j.saa.2018.09.040Citations: 1data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2019-08-18References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here