Research on conservation materials and application methods for gypsum-ground secco wall paintings

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K01192
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Cultural assets study and museology
• Research Institution: University of Tsukuba
• Principal Investigator: Taniguchi Yoko 筑波大学, 人文社会系, 准教授 (40392550)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 二水石膏 / グラウト / モルタル / 遅延剤 / セッコ

Outline of Final Research Achievements

From the literature review, the history of the use of gypsum and lime in the region from Central Asia to West Asia has been carefully studied. There are many examples of the use of anhydrite (CaSO4) and the later the use of CaSO4.2HO. An scientific study of the wall paintings in the church of St. Simeon in Cappadocia, Turkey confirmed the use of high purity gypsum, and LC-MS and ELISA analyses provided new insights into the possibility that the paintings were painted without binding media rather than with protein-containing binders. This may suggest that the local technique was influenced by Mediterranean fresco-secco techniques, but that the use of gypsum in the countryside led to a colouring technique without the carbonation process that should have occurred.

Free Research Field

考古科学、保存科学

Academic Significance and Societal Importance of the Research Achievements

石膏に関する調査の結果を参考にして、石膏を用いた彩色技術の研究と併行し、新たな壁画などの修復用グラウト用注入モルタルの改良のための石膏の利用についても検討を行った。主に遅延性、増粘性、軽量化のための添加剤、フィラーを検討した。カビなど生物被害を受けない材料を選択した。また、石膏モルタルは液水に微溶であるため、離水をできる限り抑制する材料を検討した。特性のパラメータと添加剤の関係を精査し、グラウト材として新たな石膏モルタルを作成し、エジプトやトルコの壁画修復の現場に利用した。