by L. Beck, P. C. Gutiérrez, F. Miserque and L. Thomé
Abstract:
Pigments and paint materials are known to be sensitive to particle irradiation. Occasionally, the analysis of paintings by PIXE can induce a slight or dark stain depending on the experimental conditions (beam current, dose, particle energy). In order to understand this discoloration, we have irradiated various types of art white pigments – lead white (hydrocerussite and basic lead sulfate), gypsum, calcite, zinc oxide and titanium oxide – with an external 3MeV proton micro-beam commonly used for PIXE experiments. We have observed various sensitivities depending on the pigment. No visible change occurs for calcite and titanium oxide, whereas lead white pigments are very sensitive. For the majority of the studied compounds, the discoloration is proportional to the beam current and charge. The damage induced by proton beam irradiation in lead white pigments was studied by micro-Raman and XPS spectroscopies. Structural modifications and dehydration were detected. Damage recovery was investigated by thermal treatment and UV-light irradiation. The discoloration disappeared after one week of UV illumination, showing that PIXE experiments could be safely undertaken for pigments and paintings.
Reference:
L. Beck, P. C. Gutiérrez, F. Miserque and L. Thomé, “Proton beam modification of lead white pigments”, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, vol. 307, pp. 20–24.
Bibtex Entry:
@article{beck_proton_2013,
series = {The 18th {International} {Conference} on {Ion} {Beam} {Modifications} of {Materials} ({IBMM2012})},
title = {Proton beam modification of lead white pigments},
volume = {307},
issn = {0168-583X},
url = {http://www.sciencedirect.com/science/article/pii/S0168583X1300075X},
doi = {10.1016/j.nimb.2012.12.073},
abstract = {Pigments and paint materials are known to be sensitive to particle irradiation. Occasionally, the analysis of paintings by PIXE can induce a slight or dark stain depending on the experimental conditions (beam current, dose, particle energy). In order to understand this discoloration, we have irradiated various types of art white pigments – lead white (hydrocerussite and basic lead sulfate), gypsum, calcite, zinc oxide and titanium oxide – with an external 3MeV proton micro-beam commonly used for PIXE experiments. We have observed various sensitivities depending on the pigment. No visible change occurs for calcite and titanium oxide, whereas lead white pigments are very sensitive. For the majority of the studied compounds, the discoloration is proportional to the beam current and charge. The damage induced by proton beam irradiation in lead white pigments was studied by micro-Raman and XPS spectroscopies. Structural modifications and dehydration were detected. Damage recovery was investigated by thermal treatment and UV-light irradiation. The discoloration disappeared after one week of UV illumination, showing that PIXE experiments could be safely undertaken for pigments and paintings.},
urldate = {2017-08-01},
journal = {Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms},
author = {Beck, L. and Gutiérrez, P. C. and Miserque, F. and Thomé, L.},
month = jul,
year = {2013},
keywords = {Ion irradiation, Painting, Pigments, Raman spectroscopy, Annealing, Ion beam modification, UV treatments},
pages = {20--24},
file = {ScienceDirect Full Text PDF:E:\cmam_papers\files\767\Beck et al. - 2013 - Proton beam modification of lead white pigments.pdf:application/pdf;ScienceDirect Full Text PDF:E:\Usuarios\Administrator\Zotero\storage\SDE2BVE4\Beck et al. - 2013 - Proton beam modification of lead white pigments.pdf:application/pdf;ScienceDirect Snapshot:E:\cmam_papers\files\766\S0168583X1300075X.html:text/html;ScienceDirect Snapshot:E:\Usuarios\Administrator\Zotero\storage\BCPU2J64\S0168583X1300075X.html:text/html},
}