100-Year Paper Natural Aging Project
Background: Paper documents, like all materials age. As paper ages, it decomposes. Decomposed paper can be a problem for libraries. If libraries know why paper decomposes, ways may be found to slow or halt degradation. To speed up the process of aging in order to understand its consequences, scientists often subject paper to accelerated aging. However it is important to know whether and under which condition accelerated aging really simulates natural aging. To find this out, degradation products of naturally aged items need to be determined and compared to those of accelerated aging items.
From 1994 to 2000, the American Society for Testing and Materials (ASTM) and its Institute for Standards Research (ISR) administered a multi-institutional research program designed to develop new accelerated aging test methods that could be used to model the natural aging of any type of printing and writing paper. Consequently, 15 printing and writing papers were custom-made, ranging from 100% cotton to high-lignin, and from acidic to alkaline. The accelerated aging studies addressed the effects of several environmental parameters on the aging of the papers: temperature and relative humidity (RH); light; and nitric oxide (NO2), sulfur dioxide (SO2), and ozone (O3).
However, there was no data from long-term natural aging of the papers that could be compared to the results from the accelerated aging tests to validate the accelerated aging models. Therefore, ASTM/ISR engaged a group of 10 libraries/archives willing to store sets of the 15 custom papers for 100 years, and four research laboratories to conduct periodic testing of the papers. "The Long-Term Natural Aging of Printing and Writing Papers" project began in 2000.
Contributing Studies: Shahani, C.J.; Lee, S.B.; Hengemihle, F.H.; Harrison, G; Song, P.; Sierra, M.L.; Ryan, C.C.; Weberg, N. Accelerated aging of paper: I: Chemical analysis of degradation products, II: Application of Arrhenius relationship, III: Proposal for a new accelerated aging test. Preservation Research and Testing Division, Library of Congress, Washington, DC; June 2000. Available from the American Society for Testing and Materials (ASTM).
Project Description: The objective of this multi-institutional, collaborative project is to store sets of custom-made, 20th century printing and writing papers at different libraries/archives, monitor the environmental conditions, and conduct physical and chemical analyses of the papers over a 100-year period from 2000 to 2098. The current role of the Library of Congress (LC) is: to send annual notices to all libraries/archives to remind them to complete annual data sheets and to send the data to the LC and to the US National Archives and Records Administration (NARA); to send notices to all libraries/archives reminding them of when testing is to occur; to conduct fold endurance tests of all samples sent from the libraries/archives; and to store samples of all papers in refrigerated dark storage.
The 15 papers are stored in 10 different libraries/archives in which the temperature and RH, artificial lighting, and levels of NO2, SO2, O3, and acetic acid (as funds permit) are recorded. The four collaborative research laboratories developed the following schedule, for physical and chemical tests, of the papers: 2000, 2003, 2008, 2013, 2018, 2028, 2038, 2058, 2078, and 2098.
Outcomes/Findings: This is a 100-year project in which the cumulative data acquired over the course of the project will be compared to the data from the accelerated aging experiments conducted in the original ASTM/ISR project at the end of the 100 years. To date, tests for 2000 and 2003 have been completed.
Support: Library of Congress Preservation Directorate
Acknowledgements: The Library acknowledges the three other collaborative research laboratories at the following institutes: Canadian Conservation Institute (Canada), Rochester Institute of Technology/Image Permanence Institute (USA), and the USDA Forest Service Forest Products Laboratory (USA). We also acknowledge the 10 libraries/archives where the papers are stored: Arizona State University (USA), Canadian Conservation Institute (Canada), Columbia University (USA), National Archives and Records Administration (USA), National Library of Medicine (USA), University of British Columbia (Canada), University of California-Berkeley (USA), University of Florida (USA), The University of Texas at Austin (USA), and Washington University (USA).
Update and Images: Two oral presentations on the characterization of the organic compounds present in the ASTM/ISR papers were made at the 18th Triennial Meeting of the International Association of Forensic Sciences, New Orleans, LA, July, 2008, and at the US Secret Service Forensic Services Division, Washington, DC, July 2008.