Conservation around the Millennium (Hungarian National Museum, 2001)
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3. Effect of cleaning with citrate on Barbarigo’s mantle CLEANING The surface of the painting was covered with a layer of dust. Glue used at the detaching remained on the surface at several spots and it bound the occasionally deposited sand and plaster grains. These remains were removed with softening, mostly mechanically. After moistening them several times, the old glue layers softened enough to afford mechanical removal without damaging the object. The fine but disturbing impurities that could not be “reached” by the earlier cleaning still reduced the visual effect of the painting. They could be removed with cleaning substances diluted in water. We mainly used 10% solution of triammonium-citrate with the addition of little carboxy-methyl-cellu- lose (CMC). We left the mixture on the surface for ten minutes in average, then wiped it off with a moist sponge. No change could be detected during the treatment, next day, however, when the painting had dried, the surface appeared to be dramatically cleaner and more colourful. CONSERVATION Having examined the frescoes, mounted on a double layer of canvas, we decided to leave the lining as it was. The stretching edges of the paintings would have behaved in the same way as paintings on canvas that had been stretched for a long time, so we followed a similar routine as used at canvas paintings. The tests showed that the 10% solution of Paraloid B 72 in ethyl-acetate saturated the painting in the whole thickness. So after cleaning, we consolidated the wall painting mounted on canvas with the above solution from the back side and sometimes also from the painted surface. The reinforced wall paintings could be taken down from the stretchers. Where the surface seemed to be yet too weak, we fixed it with the Klucel M2 diluted in alcohol. We had to reform the stretchers as well. Up to now, namely, the frescoes were handled as canvas paintings. And they behaved accordingly, flapping at a touch of draught. The canvas edges weakened and they were in a critical condition at the spots where they were folded over the stretchers. After strengthening, the paintings were taken down from the stretchers to reinforce the stretching edges. We applied the so-called “strip-lining”. Strips of fresh canvas were glued onto the stretching edges with Beva 3713, which was strong enough to carry the weight of the next stretching. 46
