Tillfällig partiell isolering av limfärgsbemålat trä vid behandling med fuktbaserade metoder - en jämförande studie av cyklododekan och mentol

Abstract

This thesis examines two volatile binding medias and their capacity to partially isolate distemper paint on wood during treatment with aqueous methods. The objective was to ascertain whether these methods were applicable in the context of the thesis and, if so, to determine whether a practical method, primarily suited to in situ conservation, could be identified. In order to assess the capacities and limitations of the respective substances, initial experiments were undertaken on test surfaces with distemper paint. Paints were prepared with both animal- and vegetable adhesives, respectively, in which the PVC was also adjusted. These measures ensured that the test materials where characterised by conditions also found among authentic materials. The isolating capacity of the substances was evaluated, in conjunction with aqueous treatment with both natural and synthetic adhesives, using various application forms and -methods for the respective isolators. Comparative ocular and microscopic assessments of changes in the distemper paint’s visual appearance were also executed. These evaluations indicated that several methods may be applicable, although in differing contexts. Based on the objective of the thesis, the most relevant method was selected for use in the case study. The authentic material used in the study consisted of selected material from three ceilings with decorative paintings made in the 1700s, included in Jönköping Museum’s collection. A saturated solution of menthol in petroleum spirit (4:5) was brushed on to a limited area in the centre of the distemper paint layer. The surface could, subsequently, be treated with a gelatine solution (2.5%), without restriction, through the partially insulating film. This process did not risk any discolouration in the transition between the treated and untreated surface. Approximately one month after the application, at which point a complete sublimation could be assumed, further findings regarding the surfaces were again documented – both those utilised in the initial experiments and those utilised in the case study. An ocular inspection of the test material yielded very good results, while the authentic material gave a somewhat “milky” impression. However, upon microscopic inspection, traces of menthol were visible in all cases, to varying degrees.