鹽份對福州杉保存性之影響

Influences of Salt on the Conservation Properties of China Fir

洪國榮(Kuo-Jung Hong) ； 林仁政(Jen-Cheng Lin) ； 彭秀鳳(Shiu-Fong Peng)

《農林學報》 51卷2期 (2002/06) Pp. 33-50

https://doi.org/10.30089/JAF.200206.0004

摘要

以實驗室方法，將古老和現代福州杉於飽和食鹽水中反覆浸漬－乾燥循環處理，評估試體之吸濕性、化學性質、縱向壓縮強度和膠合強度變化。含鹽試體之徑向平均膨潤率α(下標 R)(%)和弦向平均膨潤率α(下標 R) (%)皆較未處理材為低，然異方性則較未處理材為高。經天然曝曬60天後，含鹽試材之O/C比、O/H比明顯增大，心材之顏色改變大於未處理材。木材之縱向壓縮強度受鹽分影響而顯著下降；试體脫鹽處理後，木材表面之冷水抽出物與熱水抽出物含量高於未處理材。在不同相對濕度下之含水率及α(下標 R) (%)/α(下標 R) (%)比值皆相對較高，顯示木材異方性增大，尺寸較不安定。鹽分會阻礙白膠和尿素膠之膠合能力，環氧樹脂則無影響。綜言之，鹽分對長時間之古文物福州杉之劣化有一定程度之影響。

關鍵字

鹽化材 ； 脫鹽材 ； 文物保存 ； 耐候性 ； 元素分析

並列摘要

The hygroscopic and chemical properties, longitudinal compressive and shear strengths of ancient China fir and modem China fir dipped into saturated salt water and dried repeatedly were examined. The α(subscript R) and α(subscript R) values of all salted wood lower than that of untreated ones, moreover the anisotropy of salted specimen showed the greater. An apparent increase in O/C and O/H ratios and discernible color change in the heartwood of salted wood under 60-day sunlight exposure can be found, when comparing to untreated ones. Salt apparently decreases the longitudinal compressive strength of salted wood to some extent, especially for higher specific gravity wood. Comparing to the untreated wood, the cold and hot extractives of stripped salted wood surface are higher. Additionally, the greater moisture content and α(subscript R)/α(subscript R) ratio in de-salted wood were found under different humidities. Salt distinctly impairs the bonding ability of PVAc and UF adhesives to test wood, but not real for epoxy glue. Generally, the results suggest that salt has certain effects on the degradation of China fir, which used as cultural relies in long term.

並列關鍵字

Salted wood ； De-salted wood Cultural relics conservation ； Weatherability ； Elemental analysis