ABSTRACT

Stained glass restoration generally involves filling glass losses to maintain the coherence of the window and the new glasses used to fill the losses can be painted to chromatically reintegrate the stained glass panel. One of the most common painting materials on stained glass is grisaille, a paint made by mixing metal oxides with a ground lead glass. Grisailles usually have black and brown hues and are used for the creation of outlines as shadows in window glasses. Although several commercial companies sell many types of products to paint on glass, few of them present the necessary compatibility with the original materials that conservation materials must have. Debitus is one of the most renowned companies, and its grisailles are frequently used for chromatic reintegration in stained glass window restoration. Thus, the main objective of this study was to assess the long-term stability and durability of commercial Debitus grisailles. Two alteration tests were carried out, with samples placed in high humidity chambers and submerged in distilled water. The samples and degradation products were characterized by optical microscopy, µ-Raman spectroscopy, and colourimetry. In the immersion, the pH of the water was measured during the experiment, and the leached elements were analyzed at the end by inductively coupled plasma atomic emission spectroscopy. The results showed an alteration of the colour and the formation of degradation products, identified as sulphates. The solution pH was increased by the aqueous extraction of alkaline and alkaline-earth ions from the support glass of the samples. Despite these changes, it was possible to conclude that these commercial grisailles presented good durability and stability for use in conservation treatments.

摘要

彩色玻璃修复通常涉及填充玻璃损失以保持窗口的连贯性，并且可以对用于填充损失的新玻璃进行涂漆以重新整合彩色玻璃面板。彩色玻璃上最常见的绘画材料之一是grisaille，这是一种通过将金属氧化物与磨碎的铅玻璃混合制成的涂料。Grisailles通常具有黑色和棕色色调，用于在窗玻璃中创建轮廓作为阴影。尽管有几家商业公司销售多种类型的玻璃涂料产品，但其中很少有与保护材料必须具有的原始材料具有必要的兼容性。Debitus 是最知名的公司之一，它的grisailles常用于彩色玻璃窗修复中的色彩重新整合。因此，本研究的主要目的是评估商业 Debitus grisailles的长期稳定性和耐久性. 进行了两次改变测试，将样品置于高湿度室中并浸没在蒸馏水中。通过光学显微镜、μ-拉曼光谱和比色法对样品和降解产物进行表征。在浸泡中，在实验过程中测量了水的 pH 值，最后通过电感耦合等离子体原子发射光谱分析了浸出的元素。结果显示了颜色的改变和降解产物的形成，确定为硫酸盐。通过从样品的支撑玻璃中提取碱金属和碱土金属离子来增加溶液的 pH 值。尽管有这些变化，但可以得出结论，这些商业grisailles具有良好的耐久性和稳定性，可用于保护处理。