To clarify the mechanism of how the color of wood changes after being painted with oil, we measured the internal structure and optical properties in the visible light region of end‐grain linseed oil‐painted hinoki (Chamaecyparis obtusa) by X‐ray computed tomography and spectrophotometry, respectively. To compare the color measurements of different types of incident light, the color changes were measured with a spectral colorimeter. Quantitative analysis using X‐ray computed tomography images showed a positive correlation between oil penetration and the amount of oil applied. Optical property measurements showed that the largest change in reflectance was in the 430 to 480 nm region, which was affected by both absorption and transmission. We also inferred from a lack of increment in the absorption with increasing amounts of applied oil that the increase in the absorption was influenced by the increase in light passing through the walls of the wood cells.

中文翻译：

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内部结构对透明涂漆木材颜色变化的影响

为了阐明涂油后木材颜色如何变化的机理，我们测量了端粒亚麻籽油涂制扁柏（Chamaecyparis obtusa）的可见光区域的内部结构和光学性质。）分别通过X射线计算机断层扫描和分光光度法进行。为了比较不同类型的入射光的颜色测量结果，使用光谱色度计测量了颜色变化。使用X射线计算机断层扫描图像进行的定量分析显示，油渗透率与所用油量之间呈正相关。光学性能测量表明，反射率的最大变化是在430至480 nm范围内，受吸收和透射率的影响。我们还从随着吸收的油量增加吸收的缺乏而推断出，吸收的增加受穿过木室壁的光的增加的影响。