Temporary stabilization

mardi 23 Mar 2021

When the cartonnage case was cut open at the beginning of the 20th century its structural integrity was lost. Years of manipulation uncontrolled storage have left a distorted and weakened two-piece cartonnage case with the mummy . The result was delamination, creases and tears in the cartonnage case as well as lifting and loss of paint (Figs. 1 & 2). The extreme fragility of the cartonnage case made handling and transport from Brissago to Neuchâtel impossible.

Not wanting to introduce a consolidant into the paint layers before having the opportunity to study them we looked for a temporary consolidant that could be removed at a later date without leaving any residues. Preliminary analysis of the polychrome layers at the HKB by Dr. S. Zumbühl & Dr. N. Scherrer confirmed the absence of non-polar components. As a result, cyclododecane (C12H24) was chosen as a temporary consolidant. At room temperature cyclododecane, a saturated cyclic alkane, is a white waxy solid with slight odor. Applied in a melt or dissolved in a non-polar solvent it can consolidate fragile surfaces for a finite amount of time. As it sublimates at room temperature, the adhesive will diminish over days and completely disappear over weeks.

Cyclododecane was applied to the polychomy of the cartonnage with micropipettes in a melt (58°C) with small addition of petroleum ether (100-140°C boilng point) to slow down its solidification (Fig. 3). It was applied before transport and again some weeks later when the upper part of the cartonnage was lifted off the mummy with the help of a custom-made frame (Fig. 4).

Figure 1. Creases and loss of paint in the middle section of the cartonnage case
Figure 2. Creases and flaking paint in the chest area
Figure 3. Students of the HE-Arc CR consolidating the paint layers and cartonnage case with cyclododecane
Figure 4. Removal of the upper part of the consolidated cartonnage case with a custom made support frame
Figure 5. The interior of the much flattened lower part of the cartonnage case after removal of the mummy

Figure 1 et 2 : photographs Schreyer
Figures 3, 4 et 5 : photographs HE-Arc CR