New Insights into the Cleaning of Paintings

Extended Abstract—Use of Agar
Cyclododecane for Cleaning Tests
on a Frail Painting
Alberto Finozzi, Alessandra Sella, and Chiara Stefani
INTRODUCTION
The painting representing the Battle of San Martino (24 June 1859), also known as
the battle of Solferino and San Martino, probably done on cotton textile by an anonymous
author, was carried out with an unusual technique, i.e., using a monochrome sketch
painted with a slight tonal range (Figure 1). The preparation layer, the priming, and the
actual painting are in animal glue tempera, and the execution technique is poor and not
cohesive, as confirmed by the results of the analysis carried out by Stefano Volpin and
discussed subsequently.
Large areas of the painting were water stained, probably because of its original
outdoor location. The cleaning intervention served to remove the incoherent dirt from
the surface and to resolve the moisture staining problem. Different tests with different
materials and methodologies were carried out.
CLEANING PROCEDURE
Alberto Finozzi, Alessandra Sella, and Chiara
Stefani, Restauro Studio, Via Mazzini 43, Schio,
Vicenza, Italy. Correspondence: Alberto Finozzi,
albertofinozzi@libero.it; Alessandra Sella, alessandra73_4@libero.it;
Chiara Stefani, chiara_stefani_4@libero.it.
Manuscript received 19 November
2010; accepted 24 August 2012.
The first approach to the cleaning was difficult. Every intervention based on aqueous
methods resulted in moisture absorption by the surface and the formation of a new
water stain where the product was applied. Subsequently, laser cleaning was tested unsuccessfully.
Next, different kinds of erasers (kneaded, soft, and stiff erasers) were used,
and agar gels were also tested. These were applied with different methodologies, such as
(1) pregelatinized agar brushed on small areas (Campani et al., 2007), (2) agar as a stiff
gel applied for a few minutes to have the lowest level of water, (3) preliminary saturation
of the surface with an alcohol and water mixture airbrushed on the surface prior to
the agar application to prevent moisture stains, (4) preliminary saturation of the surface
with cyclododecane at different concentrations applied by brush followed with the agar
application, and (5) agar reinforced with carboxymethylcellulose to “soften” the material
and to adapt it to the painting surface. The most interesting result was obtained
using a preliminary application of cyclododecane (60% cyclododecane, 40% petroleum
ether [80°–120°C fraction] w/v) to stop water diffusion into the surface, thus preventing
moisture stains, followed by a brush application of pregelatinized agar (Hangleiter and
Saltzmann, 2008).