著者

北野 信彦 本多 貴之 佐藤 則武

雑誌

保存科学 = Science for conservation

巻号頁・発行日

no.49, pp.25-44, 2010-03-31

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The present paper is a report on the study of the red coating paints used at the Nikko-Toshogu Shrine constructed during the early Edo period, particularly those newly built in the Genna age or reconstructed in the Kan,ei age. The coating methods used were simple, just one coating layer applied directly on the surface of the structure with no foundation underneath. This is very different from the method used for repair in the middle and late Edo period in which several layers of urushi coating were applied over a thick foundation. The raw materials of the pigments used for the reddish brown coating paints were mineral hematite (α-Fe2O3) containing much quartz (SiO2). Since some old documents record that akatsuchi was offered by the Tsugaru daimyo to the Tokugawa shogunate and that toshu was used as one of the red coating materials on wooden architecture at the Nikko-Toshogu Shrine, it is our understanding that these red pigments (mineral hematite containing much quartz) are the same materials as akatsuchi and toshu. Moreover, as a result of PY-GC/MS analysis of these coating materials, it became clear that urushi coating material to which a great amount of drying oil, starch and animal glue had been added was used as coating paint. Many of these coating materials were used accordingly to suit the character or the importance of each building.