## 2 Materials and Methods  
For this study, lime wood (_Tilia cordata_), which had been damaged by xylophagous insects and recovered from historical ensembles, and which required replacement due to static considerations, was used. In choosing the wooden material, it was taken into account that polychromy, without aesthetic importance, is present on one of the faces, composed of primer (gesso), a film of a unitary red shade of paint, and a protein glue binder. The recovered wood was previously thermally and hygroscopically balanced in a controlled environment for 6 months at 20 \(\div\) 25 \({}^{\circ}\)C and RH of 55 \(\div\) 60%. Initially, the linden planks had varied sizes and humidity of 8.4 \(\div\) 9.6%. The historical wood was not processed beforehand with a machine and it was not necessary to prepare it in the same way as a new standardized wood plank. It was decided to cut and form 15 equal samples, with dimensions of L = 90 \(\times\) 1 = 130 \(\times\) h = 25 \(\div\) 27 mm; 9 of these were sectioned manually in the longitudinal direction, thus obtaining 18 samples with dimensions of L = 90 \(\times\) l = 130 \(\times\) h = 12 mm (\(\pm\)2 mm)--of which 9 samples had a surface with polychromy (P) and 9 samples were without polychromy (FP), respectively, on the back of the panel. The remaining 6 samples retained a thickness of 27 mm. In the dimensional formation of the samples, it was decided to keep a ratio of 1:5 in relation to the painted panels, which was taken as a reference, and a minimum number of 10-12 annual rings was taken into account for the samples with a thickness of 27 mm. For the sections of 10-12 mm in thickness, there should be a minimum of 5-7 rings (Figure 2). Three common liquids were selected for the art conservation treatments: water, acetone, and white spirit D40. These substances are generally used for the transfer of active biocide substances against bio-pests, such as fungi and xylophagous insects, to the wooden support. They are also used to solubilize reinforcing resins. It was necessary to observe the changes not only on samples with a thickness of 27 mm but also on those with a thickness of 10-12 mm. The 6 samples with a thickness of 27 mm were immersed, in groups of 2, in each type of selected solvent. The sectioned specimens (12 mm) were also immersed in liquids, with 6 for each solvent, respectively, employing 3 specimens with polychromy and 3 without polychromy. Partial immersion in the solvents was employed to the level of half the thickness of the samples (Figure 3). This is because, in current practice, art objects with polychromy cannot be totally immersed in solvents or treatment liquids. Figure 2: Identification of annual rings in the two types of specimens. The samples with a thickness of 12 mm were placed two-by-two in the containers, taking into account the fact that absorption was carried out from the sectioned (cut) face. In the case of the 27-mm-thick specimens, they were placed with the polychrome face outward. For the samples with a thickness of 27 mm, a quantity of 300 mL of solvent per container was used, and for the samples with a thickness of 12 mm, 150 mL of solvent was used per container. In order to be able to determine the absorption of the solvent, both the mass and the volume of liquid used/set of samples were taken into account Table 1.  
The damaged volume of the samples was calculated, and a quantity of solvent was taken into account, which, in terms of volume, should not exceed approx. 10% of the total volume of the immersed sample. The immersion time was also taken into account and limited to 15 min--dictated by simulating a treatment stage and in agreement with [PERSON] (2005), who mentions that swelling does not occur constantly and uniformly; the most important swelling occurs in the first 15 min after immersion, namely, 5.3%; at 30 min, the swelling ratio is 7%, while at 60 min, it is 8.1%.