At the same time they have developed policies and principles to guide the application of these technologies. No one technology solves all problems. Libraries like Columbia's have adopted a comprehensive approach which carefully matches the appropriate treatment to the damaged book based on the physical nature of the volume and the way it is used by readers. The preservation of embrittled materials poses a significant challenge because paper that breaks when folded cannot withstand the manipulation needed for rebinding or normal repairs. The monetary value of most volumes in the Columbia University collections does not justify spending hundreds of dollars per volume for repair, although we do have rare materials for which such expensive conservation is fully warranted.
New technologies promise a brighter future for our collections.
Increasingly, North American and Western European scholarly volumes are being printed on acid-free paper that has a much longer life than the acidic paper to which we have been accustomed. Successful chemical treatments to remove acid from paper after its manufacture now exist and are being employed by a growing number of libraries, including Columbia. Deacidification cannot add strength weakened paper, however, or reverse embrittlement once it has taken place. For most books that are already too brittle to be deacidified or repaired with routine methods, the most appropriate preservation technique is to purchase a reprint. Preservation microfilm continues to be the best assurance of longevity, since the master negative of the film, properly stored under archival conditions, guarantees a lifespan of several hundred years for the content of the volume.