Leather has been used in various fields since before the Three Kingdoms period, and leather artifacts have been preserved today. Leather artifacts are affected by the environment that moisture and oil are lost, solidification proceeds, shape deformati...
Leather has been used in various fields since before the Three Kingdoms period, and leather artifacts have been preserved today. Leather artifacts are affected by the environment that moisture and oil are lost, solidification proceeds, shape deformation occurs, and damage proceeds. To restore damaged leather, it is essential to inject moisture and oil into the leather, which is done by applying detergent and softening agents in the preservation process. There are no studies on the manufacture and applicability of detergents and softening agents that can be applied to leather artifacts in Korea, such that it is difficult to preserve the leather artifacts. To solve this problem, the author made a detergent and a softening agent that can inject moisture and oil into leather and applied it to real leather to see the possibility that it can be used for preservation.
Regarding the selection of detergent, total six materials were selected by comprehensively considering domestic and foreign research data and leather composition. As the softening agent material, 5 types of fixing materials for maintaining shape and 4 types of oil were selected for injecting oil and conducted lightness and flexibility tests. As a result of the tests, glycerin and ethyl alcohol were selected as detergent, and olive oil was selected as the softening agent.
Preparation of the detergent and softening agent was carried out by adjusting the mixing ratio. In detergent, a total of 9 detergents were prepared in a ratio of 1: 9 ∼ 9: 1 mL based on volume. A total of 10 softening agents were prepared using the oil ratio from 0%to 90% to the fixing material based on wt%. For these detergents and softening agents, measurements for brightness, thickness, moisture content, flexibility, and viscosity were conducted.
Lightness measurement was performed to identify the effect of detergent and softening agent on the lightness of leather. As a result of the measurement, the higher the glycerin content of the detergent, the greater the change in lightness.
To identify the water absorption and flexibility, thickness and moisture content and flexibility measurement were performed. As a result of the measurement, when ethyl alcohol's ratio to glycerin is 4: 6 ∼ 5: 5 mL, it was identified that the absorption rate and flexibility increased to the maximum. In contrast, they were increased to the maximum at 20% ~ 40% of the softening agent's oil content.
Viscosity measurement was performed to determine the effect of viscosity on the absorption rate. As a result of the measurement, it was identified that detergent's absorption rate decreased due to the evaporation of ethyl alcohol. In the softening agent's case, it was identified that the softening agent's oil content affected the absorption rate rather than the increase of absorption rate according to the viscosity.
As a result of the detergent and softening agent experiments presented in this paper, it is important to apply the detergent and softening agent according to the important factors depending on the artifact's condition during preservation. Since artifacts passed down are sensitive to brightness and color changes, the appropriate ratio of ethyl alcohol to glycerin with little change in brightness was 3: 7 mL as a detergent, and low oil content of 0% 10% was used as a softening agent. In excavated artifacts, the proper ratio of ethyl alcohol to glycerin, which has a high value for increasing flexibility, was 4: 6 ∼ 5: 5 mL because morphological restoration is an important factor. As a softening agent, it is believed that a softening agent with an oil content of 40% is suitable.
Based on these results, the mixing conditions for each ratio of detergent and softening agent prepared for leather preservation were presented, and the possibility of use was found in this paper. Basic data of leather preservation treatment were established. It is expected that various preservation materials can be prepared for leather artifacts excavated and passed down if additional material addition and subtraction experiments are conducted to ensure stability and minimize brightness changes through long-term monitoring of leather applied with detergent and softening agent in the future.