The use of micro‐Raman spectroscopy in architectural paint analysis

Abstract

Architectural paint analysis is an important technique for establishing the palette of historical paint colours, and reconstructing how a room or a facade might have looked at an earlier time. In its simplest form, it has often been achieved by using paint scrapes, which involves revealing a stepped sequence of layers of paint using a blade or solvents. Cross-sections are used as an alternative to, or in combination with, scrapes. Mounted cross-sections can be examined by optical microscopy. Accumulated layers of paint, wallpaper or other applied decorative finishes can be defined from their textures and colours. Knowledge of the identity of the components in paint layers can be used to reconstruct a certain paint and also to date the paint layers. It is demonstrated that micro-Raman spectroscopy combined with optical microscopy and low-vacuum scanning electron microscopy-energy-dispersive spectrometry are versatile tools for the characterization of pigments and fillers in cross-sections from architectural decorations. The paper gives an example of the examination of an interior decoration from a historical building.

Non-destructive analysis and testing of museum objects: An overview of 5 years of research

“…In a similar way to XRF equipment, instrumental developments have led lately to the availability of A-Raman instruments. Kendix et al [47] used such instrument for the study of architectural paint to date wall paint from the ''Landhaus Bauer'', a country house in Hamburg created by the Danish neo-classical architect C.F. Hansen.…”

Detecting Art Forgeries: A Problem-Based Raman Spectroscopy Lab

“…A variety of optical spectroscopic techniques find use in the chemical analysis of artwork. − Optical spectroscopic techniques such as infrared (IR) absorption, , UV–visible reflectance (UV–vis), fluorescence, , and Raman spectroscopy allow molecular-level analysis of artwork and are particularly appealing because they are at most microdestructive, as compared to more destructive techniques such as laser-induced breakdown spectroscopy (LIBS) or inductively coupled plasma–atomic emission spectroscopy (ICP–AES). In addition, some of these spectroscopic molecular analysis techniques require only optical access to the sample, making them especially well suited to noncontact examination of artwork (e.g., paintings behind glass).…”

“…The specificity of Raman spectroscopy in particular has proven useful when determining the composition of both inorganic and organic pigments. − Most pigments are easily distinguishable by their Raman spectra when compared to a reference library . In addition, because the location of vibrational peaks in a Raman spectrum is independent of the excitation wavelength, lasers with wavelengths in the near-infrared region can be used to limit fluorescence while preventing damage to potentially priceless artwork.…”