Vol. 24, No. 13	February 1, 1999

Test of Time Is Applied to Paper as 100-Year-Old Study Begins in Butler Library

BY LAUREN MARSHALL

With the start of 1999, Columbia's Preservation Division is taking part in a century-long international experiment on how paper ages.

Fifteen volumes of bound paper, almost 4 inches thick, have been placed among the books in Butler Library's off-site storage area and will be checked periodically by scientists to monitor the effects of time on the paper. Each volume consists of bound blank pages made of 15 different types of paper. The various papers include wood-pulp based, cotton-based, bleached, unbleached, acid and alkaline.

The project, monitored by the American Society for Testing and Materials Institute for Standards Research, is one part of a two-step initiative designed to identify the types of paper with the most longevity.

In addition to the 100-year experiment, five research laboratories currently are conducting shorter-term experiments on the fundamental mechanisms of paper aging. They hope to develop accurate predictions of paper longevity through accelerated aging tests. Methods of acceleration include elevated exposure to light, common pollutant gases and increases in temperature.

The results of the 5-year study, to be completed in 2000, will be compared to the results of the long-term aging study to confirm predictions of the longevity of certain kinds of paper and to establish accelerated paper aging standards for future experiments.

The two experiments also seek to confirm the observation-based theory of book deterioration accepted by most book preservationists and librarians: that acidic paper, especially when made of wood pulp, becomes brittle more quickly than alkaline paper. Columbia is one of 10 institutions, representing a variety of climate regions across the United States and Canada, that have volunteered to store the paper volumes under controlled conditions until the year 2100.