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

概要

Conservation and Restoration of Western Paper

Photos 4-6 Ink corrosion, National Archives of Mexicosolution, penetrating between the fibers ofthe support and becoming permanent inthe paper. If it is used in the insoluble orferric phase (after a few weeks), it behavessimilarly to a pigment suspension. 2 Still inthis second phase, the ink would be insolubleand permanent.Ink corrosionThe damage that iron gall inks can causein the paper support can be influenced byinternal and external factors. Some internalfactors are the composition of the ink andthe proportion of its components, thecharacteristics of the paper (type of pulp,presence of certain sizing and fillers, as wellas the thickness and possible coatings), theoxidation state of the ink when applied(ferrous or ferric), the amount of ink applied,and the instrument used for writing ordrawing. 2, 9 Regarding extrinsic factors,relative humidity, temperature and constantmanipulation of the documents have provento be the most important. 9By studying documents with iron gall inksand their degradation over time, in additionto the research of historic recipes, it is knownthat ferrous sulphate was commonly addedat higher amounts than the recommendedor needed amount to react with the gallicacid, in order to obtain a darker ink. 1 Asexplained below, this will also be a decisivefactor in the damage mechanisms of irongall inks.Even some recipes recommended addingmore ferrous sulphate if the color of the48