ブックタイトルConservation and Restoration of Western Paper

概要

Conservation and Restoration of Western Paper

cause of paper oxidation is aluminumsulfate. Aluminum sulfate is often usedas a binder for sizing, which prevents inkfrom running, in the course of the paperproduction process. When aluminumsulfate is hydrolyzed in paper, sulfuric acidis produced and it causes oxidation. It alsodamages the fiber of the paper (cellulose),and then the paper becomes tattered.The second harmful form is oxidationthat is caused by sulfur dioxide and nitrogenoxide contained in the air. Sulfur dioxideis caused by the burning of fossil fuels,and nitrogen oxide is produced due toautomobile emissions. They react withwater to form sulfuric acid and nitrous acidrespectively, which eventually leads to anacceleration in the oxidation of paper.Thirdly, the migration of substances fromsomething with which the paper has comein contact should be noted. The backingused or a bookmark inserted betweenpages are common causes. In any case, it isacid migration that occurs due to contactbetween poor-quality material and thepaper.- FoxingFoxing is a general term for brown stains,which appear on paper. It may have manycauses such as mold, bacteria or metal.- Insect damageNeedless to say, insect damage is causedby vermin.- Ink corrosionInk corrosion is the deterioration ofpaper and parchments on which somethingis written in iron gall ink. Iron gall inkcontains tannin, an aqueous solution of ironsulfate and gum arabic, and the ink reactswith oxygen in the atmosphere, so that theink adheres firmly to the substrate (paper orparchments) as if it was imprinted, and doesnot wash away with water. However, thischaracteristic may cause the degradation ofthe paper at the same time. This is oxidativedegradation due to sulfuric acid containedin the ink, which brings about the hydrolysisof cellulose, a main component of paper.In another example, the degradation ofcellulose is caused by a reaction, whichoccurs because of the iron ions acting as acatalyst. When such degradation progresses,the writing and surrounds may becomePhoto 1 Document from the early 19th centuryPhoto 2 Degraded signature writtern with iron ball ink6