Developement of New Evaluation Method of Environment by using Metal Thin Films

良好的环境被认为可以保护文化财产，如金属工艺品、木雕、绘画、布料等。这种良好的环境会阻止文化财产的腐蚀和/或退化。到目前为止，已经通过测量湿度、有毒气体和其他危害来评估环境。然而，从文化财产被侵蚀的角度来看，这种评估方法是不存在的。本研究的目的是从文化财产材料的角度开发新的环境评价技术。同时，也是研究文化材料表面反应的对象。主要研究结果如下：(1)利用溅射到玻璃衬底上的金属薄膜，如Ag、Cu、Fe、Co，以及这些合金来评价腐蚀环境。薄膜在不同环境下曝光后，用分光光度计测量金属薄膜表面的反射率。例如，银薄膜的反射率随时间呈线性下降。这是由于金属膜的表面腐蚀造成的。坡度随环境质量的不同而变化。因此，可以通过测量反射率来判断环境的好坏。利用这一新技术，研究了季节、风速、天气等因素的影响。(2)研制了体积小、重量轻、成本低的反射率测量装置，测量效率高。(3)研究了文化属性材料的表面反应，阐明了一些腐蚀机理。

Good environment has been expected to conserve the cultural properties, for example, metallic crafts, wood image, paintings, cloth, and the others. Such good environment interrupts the corrosion and /or degradation of cultural proper-ties. Until now, humidity, poisonous gas, and other hazards have been measured to evaluate the environment. However, the evaluation method, from the side of cultural property which is corroded, does not exist. The object of this investigation is to develope the new evaluation technique of environment from the side of cultural property materials. At the same time, it is the object to investigate the surface reactions of cultural materials. The obtained results are as follows.(1)By using the metallic thin films, for example, Ag, Cu, Fe,Co, and these alloys, sputtered onto the glass substrate, are used to evaluate corrosion environment. After the thin films were exposed in various circumstance, the reflectane from the metal thin film surface is measured by spectro photometer. For example, the reflectance of Ag thin film decreases linearly with increasing time. This is due to surface corrosion of metal film. The slope changes by the quality of environment. Therefore, good or bad of environment can be determined by measuring the reflectance. By this new technique, the effects of season, wind speed, weather, et al. have been clarified.(2)Small size, light weight and low cost apparatus to measure the reflectance is developed, It is confirmed that the efficiency is high as a result of measurement.(3)Surface reactions of the cultural property materials have been investigated and some of corrosion mechanisms are clarified.