## 3 Results
### Documentation of Wax-Resin Removal by TSP-GC/MS  
The untreated mock-up weighed 0.058 g/cm\({}^{2}\); after infusion with the wax-resin mixture, the weight increased to 0.092 g/cm\({}^{2}\). After the wax-resin extraction and solvent evaporation, the mock-up weighed 0.060 g/cm\({}^{2}\), indicating that approximately 94% of the wax-resin mixture had been extracted by the process. Comparison of the TICs of samples from _Radisles_ before wax-resin infusion and after extraction confirms that some wax-resin material remains detectable in an after-extraction sample (Figure 4). In particular, peaks attributable to long chain fatty acids (tetracosaonic acid ME to dotriacontanoic acid ME) and one peak related to dammar (20-hydroxy-3,4-seco-4(28),24-dammaraden-3-oic acid) are detected in the after-treatment sample [25; 26; 27]. The majority of peaks that show a decreased intensity in the after-extraction sample are derived from the acrylic ground, indicating that unequal ratios of ground and surface paints were present in the two samples. The cross-section samples seen in Figure 2 show that the ground and paint layers are variable in thickness, so variability in ground-to-surface paint ratios between any two samples can be expected. The peak area for the methyl ester 18:1 is noticeably lower in the after-treatment sample compared to the peak for 18:0 ME, as is that of nonanediolic acid (although to a much lesser extent), suggesting that some of the original components of the paint film may have been extracted along with the wax-resin material. However, care must be taken in this interpretation, as the cross-section samples in Figure 2 show that there is significant variation in the thickness of paint layers and pigments, including zinc white, which can have a significant impact on the oxidation and polymerization of drying oils [28; 29; 30; 31]. The seemingly higher levels of 18:1 in the pre-extraction sample could arise from the sample having relatively more zinc white, a pigment known to prevent oxidation of 18:1 through the formation of zinc soaps [28; 29]. In order to better understand the relative removal of dammar and beeswax through the extraction process, samples of the xylene-loaded and wicking layer Evolon sheets used in each interval were analyzed by TSP-GC/MS. No materials deriving from the acrylic ground were seen in the TICs of the Evolon sheets. To account for variances in sample sizes and pyrolytic efficiency, we investigated the use of the two major pyrolysis products of Evolon, caprolactam, and BDC-diME as internal standards. First, AMDIS was used to generate the integrated signal area for all peaks in the TICs, and then, the peak areas were  
Figure 3: Total ion chromatogram (TIC) of a sample of Evolon obtained by TSP-GC/MS. Major pyrolytic products are labeled, and the peaks marked with an (*) are multimers of the polyester portion of the material. normalized so that either the caprolactam or the BDC-diME peak areas were set to a value of one; there were no significant differences in the data standardized to either species, so either caprolactam or BDC-diME can be used as an internal standard. Figure 5 shows the TICs of the xylene-loaded Evolon sheets from each round normalized to the BDC-diME peak (note that the TICs are vertically offset to improve legibility). The peaks of species associated with wax and dammar are most intense in the X sheet, the one that was first placed in contact with the mock-up. The relative amounts of wax-resin species decrease with each change-out of sheets, with very little wax-resin seen in the X5 sheet. The TICs from the wicking layer Evolon sheets are not shown, but follow the same trend, with W having the highest amount of wax-resin material and W5 having barely detectable amounts. In their treatment of the Braque painting, [PERSON] and [PERSON] had noted that the capillary action of the wicking layer Evolon was more effective than the suction from the vacuum table in the removal process [9].