Nano2: Nanomaterials as a new approach for efficient treatment of historical documents damaged by ink corrosion

In the research project Nano2, funded by the Swiss Innovation Agency Innosuisse, several institutions in Switzerland have joined forces to develop an efficient restoration method to treat ink corrosion on cultural assets that combines chemical deacidification and mechanical stabilization using nanomaterials.
A total of at least 8,430,000 pages of manuscripts in the combined collections of Staatsarchiv Zürich and Zentralbibliothek Zürich have sustained ink damage. Not all objects can be handled with the current methods, especially books that contain water-soluble inks in addition to iron gall ink (stamps or handwritten additions) (Fig 1), books with valuable book bindings that are not to be rebound, and books in which only individual pages are affected by ink corrosion and no complete restoration is necessary.
To address this problem, the Nano2 process is being developed. The use of nanolime and nanocellulose for the treatment of ink corrosion is promising, since both materials have already been tested separately on paper in various forms of application and have been shown to be useful for deacidification and stabilization of paper, respectively. In this project, the two nanomaterials are being applied as anhydrous dispersions to provide a non-aqueous, local treatment of paper damaged by ink corrosion, in which the paper is chemically deacidified and mechanically stabilized. Various analyses will be used to demonstrate the effectiveness of the ink corrosion treatment and to optimize the formulation and application of the Nano2-dispersion to eliminate adverse effects (Fig 2).
The paper will present results of the ongoing project and emphasize cultural, economic, and institutional sustainability.