CHARACTESISTICAS DA COR DA MADERIA DE PINUS AFETADAS POR COMPRESS\uc3O T\uc9RMICA

Abstract

The goal of this study was to determine the effects of thermal modification and hot-pressing on the colour characteristics of pine wood as bio-resource. The experimental wood boards with dimensions of 250 mm in width by 500 mm in length by 18 mm in thickness were thermally compressed at a temperature of 120\ub0C or 150\ub0C, press pressure of 5 or 7 MPa for 60 min in a hot press. Results obtained in this study showed that the colour characteristics of the pine wood boards were affected by press pressure and temperature. The resin leakages significantly increased the chromacity (a* - 25.99 and b* - 43.18) of the treated wood samples. Thermally compressing caused browning of wood colour, which rate increases with pressure at high temperature conditions.O objetivo deste estudo foi determinar os efeitos das modifica\ue7\uf5es t\ue9rmicas e prensagem a quente sobre as caracter\uedsticas de cor de madeira de pinus como bio-recursos. As t\ue1buas de madeira com dimens\uf5es de 250 mm de largura por 500 mm de comprimento por 18 mm de espessura foram comprimidas termicamente a uma temperatura de 120\ub0C ou 150\ub0C, a press\ue3o de 5 ou 7 MPa durante 60 min em uma prensa quente. Os resultados obtidos neste estudo mostraram que as caracter\uedsticas de cor das amostras de madeira de pinus foram afetadas pela press\ue3o e temperatura da prensa. A resina de fugas aumentou significativamente o chromacity (a * - b * e 25.99 \u2013 43.18) das amostras de madeira tratada. Compress\ue3o termica causa escurecimento na cor da madeira, o que aumenta em condi\ue7\uf5es de press\ue3o e alta temperatura