西藏博物馆馆藏板结藏经《松赞干布遗训》的修复

Restoration of a blocked Tibetan manuscript named Pillar Testament of Songtsen Gampo in Tibet Museum

《松赞干布遗训》为西藏博物馆藏一件15世纪梵夹装手抄本,入藏前曾遭水侵致整体板结为四沓。文章描述了这件板结藏经的装帧、纸张等物质特征及破损状况,并详细介绍了所采取的分揭、清洁、补缺、加固、平整等修复处理方法。修复过程中根据藏经文物的具体特征,在一般修复方法基础之上对操作细节进行了设计和调整,包括借助SYMPATEX进行润潮、使用超细纤维布进行清洁、染纸时对湿纸进行揉搓、将刷糨后的补纸预先晾至半干,以及对补处和经叶进行差异性润潮等。修复工作取得了较为满意的结果,相关经验能够为同类文物的保护修复提供一定参考。

The Pillar Testament of Songtsen Gampo,a 15th century Tibetan manuscript,was blocked severely due to water damage before being collected by Tibet Museum.During 2017 to 2019,the National Museum of China was commissioned to carry out conservation and relevant research.The manuscript is assembled in a pothi form,which is a typical bookbinding form in Tibet,with loose oblong leaves and a protective wooden board(the back board is missing).The first and last leaves serve as the inner covers with multi-leaf structures fixed by paper clips and exquisite hand-painted illustrations.The leaves of the manuscript are beige Tibetan paper,made from 100%Stellera fibers of Thymelaeaceae family according to the dyeing reaction and morphological characteristics.Two or three pieces of paper were pasted together to form one flat and smooth leaf.A thick coating on the surface was observed by microscope,indicating that the leaves had been coated and polished.Blocking was the major damage.Except the first three leaves,the manuscript was blocked into four pieces with various thickness from 0.4 to 1.8 cm.Mould was distributed mostly on the margins of the leaves,presented as bright yellow halos and dark brown spots,which were identified as Cytospora chrysosperma based on morphological data and molecular sequence.In addition,there were also water stains,fragility,losses and other damages,increasingly severe from front to back and from left to right.It is inferred that the water invasion started from the back and the right side of the manuscript.The restoration procedures included separating,cleaning,filling,reinforcing,moistening and flattening.The moisture permeable material SYMPATEX was used for moistening before separating,and the moistening time and separating strategies were adjusted according to different blocking conditions.Finally,162 leaves were separated.To remove the dust,mould,and deposits on the surface of leaves,a vacuum cleaner,a scalpel and other tools were applied for preliminary cleaning,and microfiber cloth was used for further cleaning after local testing,which is especially useful for fine dust and mould embedded among the fibers.To repair the losses and fragility on the margins of the leaves,a kind of handmade Tibetan paper,named Jindong Paper made in Nang County,Tibet,was selected.The paper is much thicker than commonly-used repair paper and has different textures on both sides,so the wet paper was balled and stretched after the application of pigments to make the dyeing more uniform and inartificial.The missing parts of the leaves were filled and overlapped both on the front and back sides.Paste was applied onto the filling paper,which would not be put onto the missing areas until it became half-dry to avoid tideline.The vulnerable areas were reinforced with a thin layer separated from Jindong paper.Before flattening,SYMPATEX was also used for moistening.Considering the different shrinkage properties of repair paper and original leaves,the filling areas were moistened locally first and then the whole leaf was put into the SYMPATEX damp pack to moisten.The restoration has achieved satisfactory results.During this work—from moistening,separating,cleaning,filling,reinforcing to flattening—considering the distinctive characteristics of the Tibetan manuscript,many delicate designs and adjustments were made,based on restoration technologies for general paper-based objects.Some new thoughts could thus be provided for the restoration of similar objects.