Since ancient times, Ma(麻) fabrics such as hemp and ramie have been used as backgrounds for cultural properties of paintings and covers for cultural properties of historical records. A lot of Buddhist paintings made by the people in the early Joseon...
Since ancient times, Ma(麻) fabrics such as hemp and ramie have been used as backgrounds for cultural properties of paintings and covers for cultural properties of historical records. A lot of Buddhist paintings made by the people in the early Joseon Dynasty remain, and after the Japanese invasion, it was used as a base material for Gwaebul with the appearance of large Buddhist paintings. In the case of classical books, hemp cloth was used for books such as Uigwe (儀軌), Seungjeongwon Diary (承政院日記), and Daejang (大帳), which were books produced by the royal family. Ramie was used as a background for literati paintings by the gentry during the Joseon Dynasty, along with the background of Gwaebul.
Painting and paper cultural properties are damaged for various reasons. In the case of biological damage, most of the defect forms are atypical, and the width of the defect is narrow, making it difficult to fill. In addition, old painting cultural properties are accompanied by deterioration due to chemical and optical causes such as temperature, humidity, and light, and it is difficult to select filling fabrics because the strength of the fabric is lowered.
In order to fill in the missing parts of cultural properties such as paintings and papers, a filling material with weaker strength than the base material of the relics should be used, and the use of appropriate materials is very important to prevent secondary damage to cultural properties after preservation treatment. In particular, a scroll relics stored after being rolled can cause problems due to the difference in strength between the filling material and the relic base material when new fabrics are used to fill the defect.
Ma(麻) fabrics are strong, thick and tough, so it is difficult to use fabrics that have not deterioration in the preservation process. When new fabric is trimmed and filled as in the existing filling method, it is often difficult to harmonize the precise molding according to the shape of the defect and the location of the warp and weft yarns, resulting in a sense of heterogeneity. Therefore, there is an urgent need to study Ma(麻) fabric filling materials that are visually less uncomfortable and are easy to process.
In the case of silk, active research has been conducted since the 1960s when electron beam degradation silk began to be studied in Japan. In Korea, it has been preceded by Oh Joon-suk (2011), Jeong Min-hee (2020), and Ahn Deok-hwan (2022). In addition, there is a tendency to produce and use deterioration silk at the site of cultural heritage conservation treatment, but in the case of vegetable fabrics, deterioration research to fill cultural heritage has not been conducted. For the above reasons, it is urgently required to find an efficient deterioration method for Ma(麻) fabric, and to prepare basic research by measuring and comparing the change in fiber strength and discoloration. Furthermore, it is necessary to explore and establish a method of evaluating the usefulness of deteriorated Ma(麻) fabric when used for preservation treatment.
The deterioration method proceeded with UV deterioration and dry heat deterioration. Short-wavelength ultraviolet rays (Ultraviolet-C; UV-C) was selected as the degradation method by referring to the results of previous deterioration studies and preliminary experiments. In addition, we tried to find a more efficient way to use in the conservation treatment site by comparing dry heat deterioration methods, which are mainly used in the deterioration experiment of fabric and paper. Deterioration times were equally set to 72·144·216·288 hours. The specimens are of three types: ramie, unbleached hemp, and bleached hemp and hemp cloth was bleached by applying the ramie bleaching method before deterioration to determine whether yellowing could be controlled through bleaching.
After deterioration, the test results were analyzed and usefulness evaluation was conducted for each specimen. Changes in physical, chemical, and optical properties before and after deterioration were confirmed, and all three properties showed similar patterns. The usability evaluation also showed results similar to those of the analysis. As a result of the analysis, the method that can efficiently degrade Ma(麻) fabric was short-wavelength UV deterioration. In the optical characteristics, the yellowing index was higher than that of dry heat degradation, but when visually checked, except for unbleached hemp, it was judged to be within the allowable range when applied to preservation treatment. In addition, in the infrared spectroscopic analysis (FT-IR), there was a common deterioration in absorbance after deterioration, and the spectral changes of bleached and unbleached fabrics were different.
The usability evaluation was conducted to evaluate the ease of molding and dyeing. The evaluation results were similar to the tensile strength measurement results, and molding of the UV-degraded specimen was easy. In addition, molding was possible only after 144 hours of UV deterioration, but molding was possible only after 288 hours or more of dry heat deterioration. There was no significant difference between non-degraded and deteriorated fabrics in terms of dyeability evaluation.
In this study, we tried to find an efficient Ma(麻) fabric degradation method and to prepare data that can be used as a basis for measuring the degree of Ma(麻) fabric degradation through tensile strength measurement and FT-IR analysis. In addition, the same usability evaluation as in the actual preservation process was conducted to determine the appropriateness as a filling material commonly used for relics. It is hoped that through this study, it will be possible to expand the direction in which accurate repair and restoration materials for painting cultural heritage can be secured and to contribute to the improvement of paper and painting cultural heritage conservation treatment technology.