BOOK REVIEW

In recent years, many libraries and archival institutions have recognized the serious problem of rapidly deteriorating collections of paper documents. This deterioration has been found to be directly related to the acidity of paper. To preserve and extend the life of collections and to protect them from effects of acid-related damage in the future, various mass deacidification processes have been developed. However, curators, archivists, and librarians seeking to implement mass deacidification for their collections have found it difficult to decide which of these processes best suits their needs.

The technical publications and reports on mass deacidification treatments, most of them written by specialists for other specialists, require familiarity not only with technical aspects of the processes but also with the analytical and statistical procedures used for their evaluation. To the best of my knowledge, no publication addresses the questions raised by curators and archivists, written in language understandable for people with a limited technical background. Brandt's book has filled this gap by providing a comprehensive overview of currently available mass deacidification processses and setting out their advantages and disadvantages.

The book begins with a brief description of the physical and chemical characteristics of the main constituents of paper, followed by a short history of the manufacture of pulp from wood. A concise explanation of principal mechanisms of chemical degradation of paper closes the first chapter.

The next chapter introduces the concept of acid/base equilibria as it relates to the neutralization of paper. The notion of pH and its measurements, which is fundamental to this issue, is discussed in some detail in appendix 3. The chapter further reviews, in chronological order, various aqueous and nonaqueous deacidification processes developed during the last few decades.

The core of the book consists of six sections discussing commercially available, nonaqueous deacidification technologies:

• Wei T'o (methoxy magnesium methyl carbonate) process and its variants
• Bookkeeper (magnesium oxide) process
• Akzo-DEZ (diethyl zinc) process
• Lithco-FMC (magnesium butoxytriglycolate) process
• Booksaver (ammonia/ethylene oxide) process
• British Library (acrylic and methacrylic esters) process.

All processes are presented in a common format, making comparisons easy. Each section starts with a brief discussion of the active neutralizing agent and the chemistry of the process. A description of a commercial installation and review of the treatment follow. Technical details of deacidification plants and processes are, in most cases, explained with help of photographs and suitable diagrams. These details are followed by discussion of the effectiveness of treatment and its secondary effects on deacidified paper in light of tests carried out by developers and owners and more critical results obtained by independent laboratories. At the end of each section, issues of safety and environmental impact of the process are discussed.

For quick reference, basic information about all six mass deacidification processes is summarized in a tabular form in appendix 6. Addresses of all companies marketing these processes are provided in appendix 4. As three of the treatments discussed use chlorofluorocarbon solvents, appendix 5 summarizes the Montreal protocol concerning regulation of CFCs.

Some complementary topics have been included in other appendices. Appendix 1 reviews common chemical and physical analyses for testing paper, according to French AFNOR standards, with occasional references to corresponding North American TAPPI or ASTM methods. Appendix 2 briefly discusses artificial aging and reviews standard conditions used in this procedure. In the same appendix the author attempts to explain the application of the Arrhenius equation for predicting the useful lifetime of a paper. It is unlikely that the readers will find this explanation very useful, however, as the topic is too complex and controversial to be covered in just a few lines.

This book does not provide easy answers to problems of conservation and preservation of book collections. In the introduction the author warns that the book is not a guide to choosing the best mass deacidification treatment but rather a basis for reflection by library and archival curators, book restorers, and administrators involved in implementing mass deacidification policy. In the conclusion, the author makes it clear that none of the currently available treatments meets all the criteria of an ideal process and expresses some doubts about the homogeneity and effectiveness of some treatments and about the impact of air pollution on deacidified papers. At the same time, she refers to several studies in progress that may shed more light on these issues. One of them is a comparative study of books treated by the Wei T'o, FMC, and Akzo processes, carried out by the Canadian Conservation Institute. I have been actively involved in this project since its inception.

The book, originally written in French, was translated into English and published in a bilingual English/French edition, a feature likely to expand its readership. The French origin of the book can be spotted in the English version in the form of a few untranslated French words and an occasional French description of a drawing. One drawing (in both versions) is described entirely in German. These minor deficiencies do not override the importance of the information provided and its generally consistent presentation.

In summary, the book is a useful compendium of information about commercial mass deacidification processes compiled from different sources (more than 80 are cited in the footnotes). Brandt has done excellent work in organizing the available technical and scientific data and presenting them in a manner comprehensible for nonspecialists. Even as results of subsequent research begin to appear, this book continues to be a useful resource for those involved in preservation of our written heritage.