吸湿過程にある木材および木質材料の厚さ方向の水分分布の経時変化（第1報）: スギ材の含水率分布の非破壊測定

摘要

Changes of moisture content profiles in the radial direction of sugi 11-mm-thick blocks in adsorption phase were measured nondestructively using X-ray densitometry method. It took only 19 h or less from oven-dry condition to equilibrium moisture content 6 % at the surface part, whereas it took 100-200 h at the core. The higher was moisture content of the samples, the more time was needed for equilibrium. The standard error with the resolution of 6 pixel / mm was 0.7 percentage point at oven-dry condition, and 2.0 points at 9 % moisture content. 20℃ temperature difference between the sides seemed to be equal to 5 percentage points moisture content difference as a driving force. It is thought that Soret effect caused by temperature gradient cannot be ignored in terms of water migration in the radial direction below the fiber saturation point.%（1）スギ内部の含水率分布を解像度6 pixel／mmで測定したときの測定誤差は，試験体の含水率が0％のときに0.7ポイント程度，含水率9％のときには2ポイント程度と考えられた。