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

概要

Conservation and Restoration of Western Paper

hydroxide. This acts as a buffer and slowlyneutralizes the acidity in the paper.Paper documents are placed inside themass chamber where they are exposed toa gentle flow of liquid. As stated in theLibrary of Congress Technical Specificationsfor Mass Deacidification, paper items withminor tears and cracks can undergo thetreatment but there must be no detachedcover, no loose and torn leaves, no stackedleaves and no papers that are too fragile. 26The Bookkeeper process is available asmass deacidification in chambers and ashand spray. Single sheets up to the sizeof newspaper print can be placed in thechamber, but large format sheets suchas maps and papers that are fragile aredeacidified using the spraying method.8. Benefits of Minor RepairsIn the Bookkeeper deacidification process,items with minor damage are rolled witha sheet of paper and clipped together asprotection before placing inside the chamber.Items that may be further damaged by thegentle flow of the deacidification liquid areinitially treated for minor repairs in order toensure a safe deacidification treatment.The PTJ conducts minor repairs foritems in risk of damage when undergoingdeacidification treatment. For instance,mending with Japanese paper and wheatstarch paste, or resewing with linen thread.It may also include the reinforcement of thecover at the hinges and joints with Japanesepaper and wheat starch paste, or theconsolidation of red rot with hydroxypropylcellulose. These minor treatments take up to2 to 3 hours per volume, while the majoritytake around 30 minutes to 1 hour. Largevolumes such as official documents (two-holeand four-hole bindings) have many pagesand treatment of each may take over 3 hours.The length of time needed for minor repairsvaries according to the type of documentand its condition.The types of treatments conducted by PTJare minor simple repairs for the purpose ofsafe deacidification. The repairs, just enoughto endure the Bookkeeper process, provealso to withstand damages while handling.Therefore the deacidification process slowsthe degradation and minor repairs improvetorn areas which both contribute to theusage of paper documentsThe purpose and methods of minorrepairs are explained and conducted withthe understanding of the owner. However,in some cases, deterioration of the item is sosevere that it is beyond the scope of simpletreatments. For example, some pages maybetoo brittle, or water damaged pages maybestuck to each other, or some may have severeinsect damages where the pages cannotbe opened. In such severe cases, we adviceclients to seek professional assistance forproper conservation treatment.9. Writing Materials in DocumentsThere is an American evaluation report onthe effect of the Bookkeeper deacidificationtreatment on various paper samples andwriting materials such as fountain pens,ball-point pens and stamps. According tothe report, gamboge (yellow color) was theonly color which showed discoloration.26