Determination of antifungal effects of wood staining and bleaching processes

The aim of this study, the determination of effect of wood staining and bleaching processes were used in finishing process on wood destroying fungi. For this purpose, different anatomical structured Scots pine (Pinus sylvestris L.), Eastern beech (Fagus orientalis L.), sessile oak (Quercus petraea L.), and mahogany (Entandrophragma cylindricum) wood species were used. The aniline (C6H2NH2), chemical (tannin (C14H10O9))+potassium bichromate (K2Cr2O7)) and Vandyke Brown (Fe2O3,MnO2 + K2Cr2O7 + H2O) were applied to the samples as wood stain and walnut color (brown) is preferred as sample color. In the bleaching process, 4 separate solution groups including 18% were prepared, Ç1 (NaOH + H₂O₂), Ç2 (NaSiO₃ + H₂O₂), and Ç3 (H2C2O4) created with 4 different chemicals. Then bleached and stained samples were exposure against Fomitopsis palustris and Coriolus versicolor and mycelium growing on wood was observed for 3 months. In order to detect the changes occurred in the samples, weight loss (TS 5563 EN 113), retention (TS 5723), density (TS 2472), hardness (ASTM D 2240), gloss (ASTM D 523) and color (ASTM D 2244) tests were applied. Additional, changes occurred on the sample surface were determined by Scanning Electron Microscopy (SEM). According to the results of the research; the wood staining process caused increase in the color values of the wood, the decrease in the glossiness and hardness values. Chemical stain has antifungal effect on decaying fungi. Bleaching process is determined that the color and glossiness values of the wood are decreased, and the hardness values are not affected. It has been determined that Ç1 and Ç2 solutions used as bleach have antifungal effect on decaying fungi.