Restoration, book repairs and paper deacidification are the measures the Swiss National Library uses to preserve the original documents in its collections.
Paper made between 1840 and around 1990 contains acids that slowly break down its fibres. Roughly 80% of the documents held by the Swiss National Library are from this period and thus at risk of acid-related paper degradation. A chemical treatment is needed to neutralise the acids and stop the paper from deteriorating.
Restoration and book repairs
Our conservation guidelines state that we focus on preventive measures for entire collections rather than restoring individual documents. If necessary, original documents are restored or repaired with minimal intervention. The aim is always to ensure that the documents remain usable rather than to carry out a full restoration. Records are kept of all the work done. Partial restorations and simple repairs of damaged documents are performed in-house, whereas more complex restorations are handled externally.
Paper deacidification
Many papers from the period between 1850 and 1980 have a high acid content due to the production process and therefore become brittle over time. The acids are neutralised and rendered harmless with the help of paper deacidification, a mass treatment in large-scale technical facilities.
The NL had its acidic documents deacidified in the ‘papersave swiss’ plant in Wimmis near Spiez between 2000 and 2014. 1.2 million documents (483 tonnes, 13.7 linear kilometres) underwent this treatment, extending their life expectancy by at least a factor of four. In this way, the NL ensures the usability of the documents for future generations. The NL checks and documents the sustainability of this measure in a long-term monitoring programme.
More on paper deacidification
2003: Erfahrungen in der Papierentsäuerung (PDF, 1 MB, 06.02.2003)Deutsche Version der Publikation: A. Blüher: Experience in Paper Deacidification. PapierRestaurierung 4 (2003): 126-161.
Further Reading
R. Altenhöner, A. Blüher, A. Mälck, E. Niggemann, A. Potthast, B. Schneider-Kempf: Eine Zukunft für saures Papier. Perspektiven von Archiven und Bibliotheken nach Abschluss des KUR-Projektes „Nachhaltigkeit der Massenentsäuerung von Bibliotheksgut“. Zeitschrift für Bibliothekswesen und Bibliographie, Sonderband 106, 2012.
J. W. Baty, C. L. Maitland, W. Minter, M. A. Hubbe and S. K. Jordan-Mowery: Deacidification for the Conservation and Preservation of Paper-Based Works: A Review. BioResources 5(3) (2010): 1955-2023.
https://bioresources.cnr.ncsu.edu/BioRes_05/BioRes_05_3_1955_Baty_MMHJ_Deacidification_Conserv_Paper_Review_972.pdf
M. Ramin, H. Andres, A. Blüher, M. Reist, M. Wälchli: Paper Deacidification: Comparative Study. Journal of Paper Conservation 10 (2009): 17-25.
A. Blüher, G. Grossenbacher: La désacidification du papier, une mesure conservatoire: quatre ans d’exploitation à la Bibliothèque nationale suisse. Support Tracé n°4 (2004): 8-20.
A. Blüher, B. Vogelsanger: Mass Deacidification of Paper. Chimia 55 (2001): 21-28.
Last modification 26.08.2024
Contact
Swiss National Library
Preservation and Conservation
Hallwylstrasse 15
3003
Bern
Switzerland
Phone
+41 58 465 00 12
Fax
+41 58 462 84 63