Development of Property Enhanced Wood by Laser Incising

为了改善木材中流体的渗透性，采用激光切割技术对杉木(Cryptomeria Japan D.Don)和豆杉(Pseudotsuga Menziesii Franco)直径150 mm的板材进行模切，以防腐的方法渗透到90 mm的正方形木材和90×210 mm尺寸的杉木(Chamaecyparis obtusa Endl.)、杉木(Sugi)、道格拉斯冷杉(Douglas-fir)和铁杉(Tsuga Heterophylla Sarg.)的2×4板材中，以浸渍酚醛树脂。用1.7kW的CO_2激光对20×220 mm的道格拉斯冷杉板材进行木材无机化学成分的合成，对2×4的云杉板材进行乙酰化处理。在防腐剂对90 mm的杉木、杉木、铁杉和花旗松木材进行渗透的情况下，脉冲激光的照射能量范围为204J(1200W*0.17s)到312J(1200W*0.26s)，可以在90 mm深的云杉木材上打出小孔。如果环烷酸锌从针孔的穿透面积占截面积的90%以上，则渗透树种(杉木和铁杉)、铁杉和道格拉斯冷杉的切割密度必须分别大于5.0×10^3孔/m~2、6.7×10~(^3)孔/m~2、44.4×10~(^3)孔/m~2，而未切割的针叶树种和道格拉斯-冷杉木材的渗透面积分别在70%和40%以下。可见，激光切割作为一种预处理方法，可以显著提高木材流体的渗透性。

To improve permeability of fluid in wood, laser incising was applied to die penetration into 150mm diameter poles of sugi (Cryptomeria japonica D.Don) and douglas-fir (Pseudotsuga menziesii Franco), to preservative penetration into 90mm square lumber and 90 * 210mm dimension lumber of hinoki (Chamaecyparis obtusa Endl.), sugi, douglas-fir and hemlock (Tsuga heterophylla Sarg.), to inpregnation of phenolic resin into 2 * 4 boards of douglas-fir and spruce (Picea abies Karst.), to composition of wood-inorganic chemicals for 20 * 220mm boards of douglas-fir and to acetylation of 2 * 4 boards of spruce using 1.7kW CO_2 laser.In the case of preservative penetration into 90mm spquare lumber of hinoki, sugi, hemlock and douglas-fir, the irradiating energy of a pulsed laser beam ranged from 204J (1200W * 0.17s) to 312J (1200W * 0.26s) to make a pinhole over 90mm depth. If it is desirable that the penetrated area of zinc naphthenate from the pinholes is more than 90% of the sectional area, the incision densities have to be over 5.0 * 10^3 holes/m^2,6.7 * 10^3 holes/m^2,44.4 * 10^3 holes/m^2 for the permeable species (sugi and hinoki), hemlock and douglas-fir, respectively though the percentages of penetrated area for the permeable species and douglas-fir without the incision were under 70% and 40%, respectively.It becomes clear that the permeability of fluid in wood can be improved remarkably using the laser incising as a pretreatment method.