紫外可见光谱结合主成分分析对文物颜料光致变色的评价研究

The evaluation of discoloration of culture relic pigments under UV Irradiation with UV-Visible spectra coupled with principal component analysis

通过模拟博物馆馆藏环境搭建了颜料光致变色研究的实验装置,采用漫反射紫外可见光谱技术对古书画、壁画等常用的朱砂、朱磦、胭脂、三绿、三青颜料在365nm紫外光照射下的变色规律进行了考察,并利用主成分分析对光谱数据进行分析,进一步对其变色规律进行研究。结果显示,朱砂、朱磦、胭脂三种颜料的光谱呈"S"型,它们对365nm紫外光的稳定性依次为朱磦、朱砂、胭脂;三绿和三青的光谱呈"钟"型,三绿的稳定性好于三青。所建立的漫反射紫外可见光谱方法为颜料光致褪色的规律及机理研究提供了新的无损分析手段。

Simulating the preservation environment of museum a device was set up to research the discoloration of pigments under 365nm UV irradiation including cinnabar,zhubiao,kermes,malachite and azurite which were used frequently in culture relics.The reflectance UV-Visible spectra were collected in various aging time of UV irradiation in order to investigate changes of the pigments with the aging time.For further study,principal component analysis was used to the spectra.The results showed that spectra of cinnabar,zhubiao and kermes are ＂S＂ shape and their stability trend is zhubiao,cinnabar,kermes;malachite and azurite have ＂clock＂ shape spectra,and pigment of malachite is more stable than azurite.The method using UV-Visible reflectance spectra is a valuable new non-destructive analysis method for researching the rule and mechanism of pigments under light irradiation.