Ebonisation is a wood surface treatment technique in which the end result is a blackened surface. We prepared radial and tangential samples of selected wood species from 4 conifers and 18 deciduous trees and determined their moisture contents. On the basis of a preliminary test, a solution of ferric acetate (10 g/l) and a solution of tannin with distilled water was prepared in a ratio of 1 : 9 (1 unit of tannin / 9 units of water). These solutions were applied to the sample surfaces and the colour changes were then evaluated visually and using the CIELAB colour system. The samples were then artificially aged by exposure to UV light, after which the CIELAB analysis was carried out again. We found that the combination of tannin and ferric acetate effectively darkened, ebonised all the wood species studied in our study. In ebonised coniferous wood, earlywood is darker in colour than latewood. Diffuse-porous hardwoods have a more homogeneous colour shade than coronary-porous hardwoods, where the inhomogeneity of the wood tissue remains pronounced. We found that the colour changes occurred only on the surface of the wood. The artificial ageing test showed that the ebonised surface is a faded ebonised surface and thus not resistant to UV light exposure.
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