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The repair and mending of parchment has taken place for thousands of years. Methods from the earliest hand stitching of tears to today's use of modern equipment to mend and fill parchment show the importance that has been placed on its preservation and conservation. ==Flattening and crease removal== Repairing curling and crease lines in parchment is generally achieved by raising its moisture content, though some modern techniques use little or no water. Wetting parchment can cause damage, though it is sometimes unavoidable. If the entire piece of parchment needs to be flattened, one technique is to place the parchment into a controlled humidity chamber with a relative humidity of 95% or more. According to Bety Haines', one important factor to monitor is to make sure the vapor has penetrated to the core uniformly, and at its own rate, and not just the surface of the parchment. Once this has happened, the use of tensioning with clips will allow creases to be eased. If just a few creases need to be eased, 80% to 90% isopropyl alcohol may be applied to the creases directly. Heavier skins may need the higher water content. The Alcohol-Water mixture is azeotropic, meaning both components will evaporate simultaneously. The solution has a lower surface tension than water, which causes the fibers to suffer less shrinkage.〔 The solution can be applied with a cotton swab and then gently pulled flat by hand. The easiest and safest method to flatten parchment is to humidify and then dry and flatten it on the vacuum suction table rather than using the clips and tensioning frame. Suction table flattening is widely employed in the United States. A fully humidified parchment is placed on a suction table at low suction and then covered with polyester film strips of varying sizes. Once the suction is turned up, the parchment is gently stretched and mainpulated until flat and then held in place with the polyester strips. After the parchment is satisfactorily flattened overall, the polyester strips are removed and replaced with a blotter or Gore-Tex sheet for further drying and flattening. After treatment on the suction table, the parchment is placed in a weighted blotter stack to further dry and flatten. Another method of localized treatment involves the use of an ultrasonic humidifier to add humidification in a controlled area. During the process, tension is gradually placed on the edges of the parchment to release the creases and then it is dried under pressure between polyester web and thick wool felts. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Parchment repair」の詳細全文を読む スポンサード リンク
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