Publication Type:Conference Paper
Source:Cleaning, retouching and coatings: Contributions to the 1990 IIC Congress, Brussels, p.98-105 (1990)
Keywords:acetone, burnt sienna, Fourier transform, infrared spectroscopy, leaching, lead white, linseed oil, oil paint, organic solvents, paint film, scanning electron microscopy, shear modulus, spectroscopy, surfaces, water
Mechanical and surface properties of paint films treated with organic solvents and water have been investigated using a range of thermal mechanical and dielectric techniques together with Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Changes in the nature of the surface after treatment were observed. The effect of water, propan-2-ol, and propanone (acetone) immersion for 24 hours, and swabbing for a few minutes, on naturally aged 12-year-old samples of lead white/linseed oil and burnt sienna/linseed oil could be measured directly in terms of change in the shear modulus of the paint films together with the accompanying change in the ratio of viscous to elastic components present in each system. Generally, the solvent-treated films became harder and showed reduced viscous components, whereas the water-treated samples became softer. There was a change in the dielectric properties of the leached films which pointed to the polar nature of the leachings. FTIR diffuse reflectance spectra supported this conclusion.