HEAT TREATMENT METHOD FOR LUMBER AND HEAT-TREATED LUMBER

To provide a heat treatment method for lumber that allows lumber not only not to be decomposed by wood decay fungi but to have dimensional stability and high durability by producing a compound such as furan exhibiting an antibacterial property by itself as exhibiting more resistivity more than that of lignin through decomposition and transformation of hemicellulouse susceptible to decomposition by wood decay fungi and like and an amorphous region of cellulose.SOLUTION: A heat treatment method comprises: a step for immersing lumber in a diluted solution of salt generating inorganic acid by decomposition through decomposition and sublimation treatments of all amount heated at 200°C or less, or coating, spraying, and impregnating the solution on the lumber; and a step for heating the lumber immersed in the solution, or coated, sprayed, and impregnated with the solution at 120 to 200°C for 72 hours or less, wherein the solution is an ammonium chloride solution with a concentration of 0.1 to 5.0 wt.%, in which a weight loss after the heat-treatment step is 3% or more to 20% or less.SELECTED DRAWING: None 【課題】木材腐朽菌等の分解を受けやすいヘミセルロースと、セルロースのうち非晶領域を分解、変成してリグニン以上の抵抗性を示し、木材腐朽菌によって分解されないばかりか、それ自体が抗菌性を示すフラン等の化合物とすることで木材に寸法安定性及び高い耐久性を与える。【解決手段】２００℃以下の加熱で全量が分解、昇華して、その分解により無機酸を発生させる塩の希薄な水溶液に木材を浸漬、又は木材に塗布、噴霧、含浸する工程と、前記水溶液に浸漬、又は塗布、噴霧、含浸された木材に対して１２０～２００℃で７２時間以内の加熱処理を行う工程とを備えており、前記水溶液は、濃度０．１～５．０重量％の塩化アンモニウム水溶液であり、前記加熱工程後の重量減少率が、３％以上２０％以下に設定されている。【選択図】 なし