Abstrakt:
The article presents negative aspects of application of toluene, solvent commonly used for strengthening impregnation treatment, on polychrome wood. The reader is introduced with matter of impregnation and solvents applied to. Results of research concerning issues important for interaction between wood and impregnation solution are presented, laying stress on toluene. Thanks to the UV-fluorescence microscopy method combined with the utilization of fluorescence markers of the applied solutions, the known fact of uneven consolidant distribution and it’s higher concentration nearby the surface in case of toluene’s solutions has been proved. The tests were conducted on wood covered with layers of priming and paint allowed to observe considerable changes of polychromy colour, affected by extraction of coloured wood constituents, caused by toluene. The rate of colour changes was restricted a little by a geled resin, from the applied solution, that thickened on the border between wood and priming layer – two materials characterized by different porosity. The observations were supported by spectrophotometric measurement. Some structural changes in priming and painting layers, such as swelling, blistering and increase of porosity were also observed as well as significant and long-lasting decrease of their softening point.