ARHIVSKI VJESNIK 11-12. (ZAGREB, 1968-1969.)

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Since the drying and disinfection was performed quickly enough the material was not damaged by mould. However, as it was handled while wet and damp and during the drying itself the material was quite badly mechanically damaged. Dampness also speeded up the action of the acid ink which "bit through" the paper in places where the text had been. This was so pronounced in some parts that some of the pages disintegrated. About two thirds of all the pages were damaged in this way. The material was restored in the following way: After tha parcels had been completely unpacked the numeration of the pages was checked. After that all the pages were neutralised with a solution of calcium hydroxide in water. The neutralised pages were then dried in the air so that the surplus calcium hydroxide would turn into calcium carbonate under the influence of the carbon dioxide in the air. In practice the neutralisation was performed in this way: as the paper was very thin to begin with, and as it was wakened by damp and acid ink, the pages could not be immersed in the neutralising solution without being protected by meshes. But it was seen that the nylon meshes themselves were not enough to protect the pages from being damaged further. Because of this page by page was first wrapped in nylon material, then put in the meshes and only then were they immersed in the neutralising solution. After about 20 minutes of neutralisation the meshes were first taken off, then the pages were partially dried in the nylon material, and finally they were dried completely in the air and then pressed in a press. By such a process of neutralisation further mechanical damage of the paper was avoided. When the neutralisation was completed the pages were sorted out. Those that were only slightly mechanically damaged were restored by hand, those with greated mechanical damage and those damaged by acid in were laminated. The paper of those pages that were to be restored by hand was first strengthened by a solution of acetic cellulose in acetone. The acetic cellulose that we used for making the solution is used for the lamination of documents, and was bought in England where it was made by the standard of the British Museum. After being coated with the solution of acetic cellulose in acetone so as to strengthen them the pages were dried and pressed again, and after that Japanese paper (seidenpapier and Inoshi) was stuck in the damaged places with the glues Tapetol and Glutofix. The pages that were to be laminated were laminated on one side only with acetic cellulose and glue (HLC Matte No, 88 Heatseal). Missing parts of the documents were filled in by Japanese paper (Okamoto Gasenshi) — picture 2 — then stuck with Coccoina glue from the side of the document that was not laminated. When the restoration was finished, the documents were bound as they had been before (pictures 3 and 4). The restored material was returned to the State Archives in Florence in July, 1968. 324