Humidification of multi-membrane parchment documents
It is not always necessary or desirable to flatten a document completely. Creases and
strong folds can be eased using the oft-described method employing 80% isopropanol
to 20% water solution. This is painted on using a fine brush along the line
of the crease with blotters and weights utilised to hold the document as it dries.
Starting at the last attached sheet and working on a blotter the creases are eased. A
blotter is placed on each membrane as it is flattened and the next sheet is turned
down to be worked on. In this way the main body of the document can be
supplicated leaving the area where the document hinges or folds adjacent to the plica.
This can then be tackled using the iso-propanol solution in the same way.