Investigation of the Cause of Brown Spots on Gofun - A Case Study of Glue Painting in Silk“Wild Ducks Among Lotus”

• Main Authors: Chang, Shu-Han, 張淑涵
• Other Authors: Tsai, Fei-Wen
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/8984m3

碩士 === 國立臺南藝術大學 === 博物館學與古物維護研究所 === 102 === There are multiple factors must be considered while facing the deterioration of an object. This research aims at the cause of brown spots on gofun paint, by a case study of glue painting. Through examinations, it is preliminarily speculated that there are some characteristic of biodeterioration on the gufan painted surface, like round, irregular shape of losses, spots with fluorescent reaction, unknown black flyspecks and holes on the silk. We can also surmise from the process of pigment-mixing may have some flaws that result in the loss on the painted surface. In order to plan and give a conservation treatment and preservation suggestion, it is necessary to clarify what cause those deteriorations on painting. It is proved by means of pest simulate experiment and pigment analysis: choosing three species of household cockroaches (Periplaneta Americana, Blattella germanica, Supella longipalpa) and gray silverfish (Ctenolepisma Longicaudata) to meet the painting’s deteriorated problem and previous storage environment. Each of the pest with sample keep in the same case in 49 days, the result of the sample is being observed and collected as contrast. GC/MS and SEM/EDS device are used for analyzing the elements of deteriorated spots. The experiment results eliminate the possibility of the effect by pests and the pigment analysis shows that the brown spots on gufun have few calcium carbonate remained. It is inferred that the ingredient of gofun in this case may be calcium hydroxide. It is because of the lacking of carbonatation leads the pigments loss and the support layer is shown, the glue remains on the surface are deteriorated, turning the color into brown appearance. For the stability, it is recommended that artists should choose gofun cautiously and increase the concentration of glue, make sure the pigment is well-binded. A rapid, well-controlled environment can decrease the effect of humidity to gofun and postpone problems mentioned above.