A Formulation for a New Environmentally Friendly Varnish for Paintings
Source abstract
Abstract
Laropal® A81 is a urea-aldehyde resin used as a varnish for paintings requiring 30%–40% of aromatic solvents to be dissolved. Considering the dangers of aromatic solvents for the environment and health, an attempt was made to replace them with less impactful and low-toxic solvents. The present research investigates a new formulation with aliphatic hydrocarbons and esters (isobutyl isobutyrate, IBIB) as an alternative to traditional aromatics mixture. Traditional and alternative varnish formulations of Laropal® A81 were studied on an inert support and paint samples to test the resin by itself and in interaction with paint film, respectively. This study aims to compare the two different formulations of Laropal® A81 by evaluating their optical, colorimetric, and stability proprieties before and after natural and accelerated ageing. Colorimetry and spectroscopic techniques (transmittance and reflectance UV-VIS-NIR, FORS, transmittance and total reflectance FT-IR, and 1H-NMR) were used for the assessment. Very promising results have been obtained with the application of the alternative formulation, with data comparable to those of the traditional formulation, paving the way for the replacement of the aromatic-based solvents traditionally used with IBIB. This allows a safer and more sustainable conservation practice with considerable benefits for the health of the operators and the environment.
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Research context
OpenAlex topics: Building materials and conservation · Cultural Heritage Materials Analysis · Conservation Techniques and Studies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
“Nello Carrara” Institute of Applied Physics of the National Research Council (IFAC-CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy
Department of Chemistry, University of Florence, Via della Latruccia 3-13, 50019 Sesto Fiorentino, Italy
Conservation Science Department, Deutsches Museum, Museumsinsel 1, 80538 Munich, Germany
Chair of Conservation-Restoration, Art Technology and Conservation Science, TUM School of Engineering and Design, Technical University of Munich, Oettingenstr. 15, 80538 Munich, Germany
Conservator in Private Practise, Via Maggio 40, 50125 Firenze, Italy
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