人為誘發紙張褐斑之探究

Effect of Artificial Induced Foxing Spots Formation on Paper-based Materials

前報証實褐斑紙樣含有寡糖類、有機酸及胺基酸等成份，據此本試驗將多種有機酸、胺基酸類溶液配合糖液之相異組合滴著於滅菌後之紙面上，並藉各種溫、濕度及pH值等處理條件，以人為方式在紙面形成褐斑。試驗結果歸納如后：單一種成分在紙面不易形成褐斑。葡萄糖（或木糖）與胺基酸之組合，造成褐變反應而在紙面呈現黃褐色，褐斑之濃淡程度與滴著糖液（及或胺基酸液）之濃度成正比。糖液配合胺基酸液，造成紙面褐變程度由濃而淡依序為糖液添加γ-胺基丁酸＞添加絲胺酸＞添加胺基乙酸＞添加β-丙胺酸＞添加鳥胺酸＞添加天門冬胺酸＞添加穀胺酸。隨褐變程度之增加，紙面之螢光現象益形明顯。因自然形成或人為誘發之紙張褐斑部位，以365nm UV燈照射，均呈現螢光現象，此簡易方法可應用於紙張褐斑之偵測。人為誘發紙張褐斑色差值之高低與處理之相對濕度呈反比之趨勢，與溫度或pH值呈正比之趨勢。誘生紙褐斑菌類之培養液經萃取後滴著於紙面上，可再現褐色斑及螢光現象。 Components such as oligosaccharides, organic acids and amino acids were found on the foxed area of papers. The aims of this paper are using varying combinations of such components dropping on disinfected papers, then treated at different temperature, relative humidity and pH value on the induced artificial foxing. The formed foxing spots on paper surface can be figured out by the number of papers’ foxing. The following conclusions can be drawn: Brown spots can not be observed on the surface of paper by single component. The combination of glucose (or xylose) with amino acids induced the formation of brown spots after treatments, the increase of brownness is parallel to the higher concentration of sugar and organic acids. The tendencies of brownness on the surface or paper induced by combination of glucose (or xylose) with amino acids were ordered sequentially : γ -aminobutyric acid > serine > glycine > β -alanine > ornithine > aspartic acid > glutamine respectively. Under UV light 365 nm exposure, distinct fluorescent phenomenon can be observed around the brown spots of paper. Detection of foxing induced by natural or artificial cause under the wavelength of 365 nm light is an effective method. The color difference values of artificially induced foxing spots is inversely proportion to relative humidity, but in direct proportion to temperature and pH value of papers respectively. Dropped the foxing inducing fungi extractives into the paper, both of brown spots and fluorescence appeared on the papers surface.

Components such as oligosaccharides, organic acids and amino acids were found on the foxed area of papers. The aims of this paper are using varying combinations of such components dropping on disinfected papers, then treated at different temperature, relative humidity and pH value on the induced artificial foxing. The formed foxing spots on paper surface can be figured out by the number of papers’ foxing. The following conclusions can be drawn: Brown spots can not be observed on the surface of paper by single component. The combination of glucose (or xylose) with amino acids induced the formation of brown spots after treatments, the increase of brownness is parallel to the higher concentration of sugar and organic acids. The tendencies of brownness on the surface or paper induced by combination of glucose (or xylose) with amino acids were ordered sequentially : γ -aminobutyric acid > serine > glycine > β -alanine > ornithine > aspartic acid > glutamine respectively. Under UV light 365 nm exposure, distinct fluorescent phenomenon can be observed around the brown spots of paper. Detection of foxing induced by natural or artificial cause under the wavelength of 365 nm light is an effective method. The color difference values of artificially induced foxing spots is inversely proportion to relative humidity, but in direct proportion to temperature and pH value of papers respectively. Dropped the foxing inducing fungi extractives into the paper, both of brown spots and fluorescence appeared on the papers surface.