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

概要

Conservation and Restoration of Western Paper

It is essential to have methodologiesin order to help prioritize the needs ofcollections and maximize resources inarchives, libraries and other institutions thathouse and preserve documental heritage.In order to do this, the conservationcommunity has adopted the predictiveapproach of risk management to assessdiverse types of collections, and documentswith iron gall inks are no exception. 12The advantage of applying risk models inthe assessment of documents with iron gallink is that not only the current state of thedocument or collection is known, but alsopotential risks are identified, predicted andfurther degradation can be prevented. Theuse of risk management methodology forthe assessment of documents with iron gallinks has been developed primarily in Canada,with Tse and Waller, who have proposedspecific models of risk assessment and riskcontrol options for iron gall inks on paper. 12To develop this model, Tse and Wallergathered research results of iron gall inksin various institutions in countries likeNetherlands, Slovenia, Austria, USA andGermany, incorporating condition ratingsand indicators generated from such research,including:A. ICN Condition Rating Chart 13Reissland and Hoffenk de Graaff,researchers from the Amsterdam InstituutCollectie Nederland (ICN), developed a fourstage rating of ink corrosion degradation,to facilitate its assessment. The four stagesof degradation proposed by Reisslandand Hofenk de Graaff for iron gall inkdocuments are: good, fair, poor and badconditions, and the examination should becarried out on the verso of the document,considering its most degraded area. 9B. Process of paper decompositiondue to the action of iron gall inks(under UV light) 14Classification proposed also by Reisslandand Hoffenk de Graaff, which summarizesin seven stratigraphic diagrams, thedegradation process by ink corrosion underexamination with UV light (356 nm).When ink corrosion begins, it is not yetnoticeable to the naked eye, but under UVlight, green halos can be observed aroundthe inked areas. This fluorescence changesto a yellow hue as the damage progresses,and when the damage is in the final stages(heavy discoloration, offsetting and cracks),fluorescence under UV light is no longernoticeable.The application of this examination canrecognize, in some cases, the beginnings ofcorrosion, when it is still not visible to thenaked eye, indicating inks with potential riskof causing this particular damage.C. Bathophenanthroline indicatorpaper for iron (II) ions 15Originally designed for the identificationof iron gall inks. Bathophenanthroline is aspecific non-water soluble indicator for iron(II) ions. 12, 15 It is a quick, sensitive (from 1ppm of iron(II)), accessible, easy to perform,and non-destructive test.The bathophenanthroline indicator paperis specific for iron (II) ions, which are51