The Alkaline Paper Advocate

Volume 4, Number 2
May 1991

Progress in Preservation

A lot has happened since the TAPPI Paper Preservation Symposium in October 1988, and it's time for an update. The following summary, drawn from the pages of the Abbey Newsletter, covers newsworthy developments over the last two or three years, except for those related to the use of alkaline paper, an important kind of preventative preservation in itself that has been well covered in this Newsletter. This summary covers 11 developments or topics, seven of which are updates of material from the 1988 Symposium. The last four topics (originals vs. copies, and three developments in conservation science) are included because they are part of the story of preservation of books and paper, although they were not covered at the Symposium.

Preservation: The Field and the Profession

Education: In June of 1990, Columbia University announced that it would close its library school in 1992. This meant closing the library school's Conservation Education Programs, which offer the only full-time training in this country for preservation administrators and conservators. The Preservation Education Programs are expected to move to another venue in 1992. Several universities have expressed an interest in having the Programs on their campus, but no decision has been made yet.

Beginning in 1993, the saw two types of training for library and archives personnel-administrative and benchwork will be offered at the Winterthur University of Delaware Art Conservation Program. The SUNY College at Buffalo is very interested in setting up a program for archive conservators, but has not progressed beyond the planning process.

Growth of the field: According to a recent survey done by the Association of Research Libraries, preservation expenditures of its 107 member libraries increased 23% in 1988-89 over the previous year; staff increased by 12.5%. Although the recession has hit many library preservation program, they are still faring better, on the average, than other departments in libraries. The number of preservation programs in libraries continues to increase because of widespread concern and support for preservation, even in hard times. Statewide preservation programs serving the needs of libraries, archives and museums are being established slowly in one state after the other. The National Endowment for the Humanities (NEH) helps them get started, by providing planning grants. New York, North Carolina, Ohio and Illinois are the states with preservation programs. The institution administering the program (usually the state library) offers advice, assistance with grant writing and microfilming programs, workshops, leaflets and manuals, and other information and education services. So far they have not set up central facilities for book mending, deacidification or other direct services.

NEH's 1989 budget was tripled by Congress over its 1988 budget to enable it to do more about the preservation crisis. The emphasis of its grant program is on microfilming. By the year 2007 it hopes to have financed the filming of 3 million library volumes. This, of course, is only a small percentage of the brittle books in this country. An effort is being made to choose the most important ones to film, but some libraries find book-by-book selection so time-consuming that they are simply filming all books in their most important endangered collections, regardless of the condition of individual books.

Pest Control

Since ethylene oxide fell from favor several years ago, there has been no fumigant suitable for use in libraries and archives that could control both microorganisms and insects. Thymol fumigation to control mold has been shown to do more harm than good, in the long run. The search for nontoxic substitutes for ethylene oxide, thymol and other familiar fumigants has continued at an accelerated pace since then, with some success. The emphasis now is an integrated pest management, which includes environmental control, monitoring for insects, good housekeeping, freezing infested materials, and limited fumigation. The approach is explained in A Guide to Pest Control (Linda Zycherman and J. Richard Shrock, eds.), which came out in November 1988 and is available from the American Institute for Conservation (AIC) in Washington, DC.

Reports of research and experience with pest control have appeared frequently in the conservation literature of the last three years. When fumigation is necessary to control insects, freezing is the current method of choice. Inert gases are seen as promising fumigants, though few institutions have facilities yet for using them. Inert atmospheres can be provided within enclosures by exhausting the air and pumping in carbon dioxide, nitrogen or argon. A fumigation bubble" adapted for this use has appeared on the market in recent months, and is still under development. It speeds the fumigation process by use of controlled heat.

An inert atmosphere can also be provided for valuable item in small airtight enclosures with an oxygen scavenger called "Ageless." The inert atmosphere it generates is said to control mold as well as insects, and also shows promise for use with hard-to-preserve museum artifacts made of rubber and plastic.

Heat has been recommended to enhance the fungicidal and insecticidal effect of gamma rays on archival records on paper, while retarding their degradative effect, but this combination of agents has not been used in the U.S. Gamma radiation alone has been used at least once here (at Johns Hopkins in 1983), but does not seem likely to catch on, partly because the facilities are not widely available, partly because gamma radiation strong enough to kill insects is known to damage paper, and partly because existing facilities are usually set up to treat food, and the operators are not keen on the idea of admitting moldy, pest-ridden boxes of archival records between the runs of beans and strawberries.

In a paper at the 1988 Symposium, microwave ovens were recommended for routine treatment of books returned to the library to kill any insects that may have gotten into them while on loan, but the idea does not seen to have been taken up by anyone. Unless they see a clear need, most librarians oppose giving potentially harmful treatments on a routine basis, especially treatments that have to be delegated to student help. (Some books have adhesives or metallic materials in them that melt, spark or char the paper if they are overexposed to the radiation. Some German books, for instance, are held together by scores or hundreds of staples, buried in the binding.)

Environmental Control

The two big reasons for controlled temperature and relative humidity in libraries and archives are to retard natural aging of the collections and to prevent the growth of microorganism, insects and animal pests. A dehumidifying "heat pipe" that attaches to air conditioners was announced to the preservation community in May 1989. It can maintain relative humidity in a safe range even in tropical climates, while reducing power bills dramatically; but so far it has been installed in libraries only for economy and human comfort, rather than for preservation.

The Getty Conservation Institute (GCI) and the National Institute of Standards and Technology (NIST) are both doing important research related to long-term storage. Last July the GCI published a report they sponsored, "Exposure of Deacidified Paper to Ambient Levels Of S02 and N02," one of a number of recent studies from various sources that have evaluated the protection offered to paper by deacidification. At the request of the National Archives, NIST is analyzing the degradation products of paper under natural and accelerated conditions, with and without S02, to identify and-characterize autocatalytic and pollution-related degradation processes that may be going on inside storage containers, and to correlate the changes going an under natural and accelerated aging. The first report of this ongoing work was issued in December 1990.

Because physical plant s are key people when it comes to environmental control in institutional buildings, and because librarians have found it hard to communicate with them about environmental control for preservation, a two-day training course in environmental conditions for libraries and archives was given February 28 - March 1, for library and physical plant administrators. It was arranged at the initiative of the Commission on Preservation and Access (CPA), a high-level organization that was formed in order to solve high-level preservation problems. The CPA's president, Pat Battin, spoke at the 1988 Symposium.

Mass Deacidification

Over the past three years, there has been a lot of research and development in the field of mass deacidification, but the use of existing deacidification processes by libraries and archives has increased hardly at all. Libraries are holding back, partly because there has never been an independent comparative evaluation of the major methods: Wei T'o, diethyl zinc, the Bookkeeper Process, ethanolamine, and (new since the Symposium) the Lithco or FMC Process. The Library of Congress issued an RFP (request for proposals, or invitation to bid on the contract) last summer, and hopes to choose among competing bids this summer. The test results furnished by an independent laboratory in connection with this bid process will be made public; that will help libraries choose a method they can trust. In Canada, the different processes will be evaluated by the Canadian Conservation Institute (CCI), a government-sponsored research facility, for the benefit of all Canadian libraries.

An admirable report by Peter Sparks, "Technical Considerations in Choosing Mass Deacidification Processes," was published in May 1990 by the Commission an Preservation and Access. (Dr. Sparks was the Preservation Officer at the Library of Congress until January 1990, when he set up an independent consulting c in the Philadelphia area.)

A method of fixing dyes by the simultaneous use of selected anionic and cationic dye fixing agents has been developed in Germany. This will permit aqueous treatments of documents, including deacidification in aqueous solutions, to be carried out on a mass basis without significant bleeding of inks and colors. Wilfried Feindt, of the Niedersaechische Staatsarchiv in Bueckeburg, is developing a machine that will use this method prior to automated washing and deacidification of documents.

Strengthening and Strength Testing

The Lithco deacidification process is said by its developer to strengthen the paper as well as deacidify it, but no clear and convincing data has been released yet on this effect.

A comparison of water-soluble strengthening agents for paper conservation was reported in Restaurator (v.10 #I) in July 1989. After aging, methyl cellulose seemed superior to the other agents, which were polyvinyl alcohol, refined sodium alginate, hydroxypropylcellulose, and refined sodium carrageenan.

Parylene, a strengthening agent which was described at the Symposium, is now offered commercially by a library binding company (ICI) for strengthening the pages of entire books, one or several books at a time.

The British Library is seeking investors for a pilot plant for its graft copolymerization method, developed for the Library by scientists at Surrey University, and described at the Symposium by David Clements.

A method for nondestructive determination of paper strength, suitable for use in library stacks, is being sought in a three-year research project under Derek Priest at the University of Manchester Institute of Science and Technology (UMIST). It may turn out to be a portable adaptation of the ultrasonic sensors used in the paper industry.

Originals vs. Copies

Now that national funding is available for microfilming of brittle books, and more and rare libraries are setting up preservation-oriented microfilming programs, concern has been growing librarians and scholars over the disappearance of the originals, which are usually discarded after they are filmed. This concern comes not only from a sentimental attachment to a familiar and convenient format, but from knowledge that certain vital information cannot be transferred to film. To help save the information inherent in colored illustrations, for instance, new methods and standards are being developed for color microfilms. An exciting digital project is going on at Cornell University, which will advance the state of the art of textual preservation; the future will be very interesting. But something is lost 4m the original is inaccessible. sow libraries, including Columbia University, have a policy of keeping most filmed originals.

Bound photocopies of brittle books are now made commercially by several companies for a rapidly growing circle of library customers. The finished product looks so much like the original (or like the original might have when it was new) that a notice has to be put in the book identify it as a copy.

In early 1989, Xerox introduced its Booksaver Copier, which has a glass platen that goes right out to the edge, allowing the library client to copy book pages even when the inner margin is narrow, without having to mash the book flat on the glass. Xerox was the fourth company in the last decade to introduce a copier designed for this purpose.

Paper Conservation Research

Enzymes: These are often used by paper conservators to dissolve old adhesives on works of art on paper. There are two significant publications on this topic, one recent and me forthcoming:

1. Enzyme Treatments: The Science and the Applications in Conserving Artistic and Historic Works" is a selected 170-item bibliography covering the period 1940-1990, compiled by Elizabeth Morse for an enzyme conference last October. (It is being made available from the Abbey Publications office, at the request of the compiler, since no other record of the conference will be published.) 2. An interim report of the CCI's long-tem enzyme study was given in October 1988 at a conservation conference in Ottawa. Twenty-one of the 29 enzymes tested reduced the degree of polymerization of cellulose in test papers. (Viscosity was used as an index of degree of polymerization.) The proceedings of this conference, Symposium 88, have not been published yet. Research is ongoing.

Foxing: This is an increasingly popular but confusing field of research at present. Every new study seems to suggest a different explanation for the color and true nature of foxing spots: fungi, rusted iron, copper compounds, Maillard reaction, and oxidation. A significant paper by Vincent Daniels in the 1988 Paper Conservator, "The Discoloration of Paper on Aging," provides a broader context for the phenomenon but does not eliminate the confusion. It suggests eight reasons, including foxing, for browning or discoloration, and proposes a common mechanism for all of them: induced oxidation, which can be detected by the Russell effect, an image produced on specially prepared photographic plates by the oxidizing material. Hideo Arai has also done significant work on foxing. His latest paper identified three organic compounds as the cause; these may be the metabolic products of xerophilic fungi.

Bleaching. In October 1988, a long-standing disagreement between paper conservators and conservation scientists over light bleaching was resolved. Conservators for years have been bleaching discolored art prints in sunlight or under fluorescent bulbs, with the prints submerged in water made alkaline with calcium or magnesium salts. They have always maintained that the alkaline water bath protected the paper from the ordinarily damaging effects of light, while the paper chemists maintained that bleaching always damaged paper to some extent. Then a research paper given at the Ottawa conference by a scientist from the Mellon institute confirmed the conservator's experience: although ultraviolet light does darken papers containing lignin, wet light bleaching does not damage paper; and the alkalinity and moisture accelerate the bleaching process.

Conservators have used oxidizing bleaches for years. Those still in general use include hydrogen peroxide, chlorite/chlorine dioxide solutions, and hypochlorites. Recently, certain reducing agents (borohydrides) have gained favor because under the proper conditions they not only do not damage the cellulose, but actually protect it against future oxidation. Bleaching agents and procedures used in conservation are described in a 38-page chapter published in 1990 as part of the AIC Book and Paper Group ' s Paper Conservation Catalog. A 15-page manual and literature review on bleaching, by CCI staff, was published in the 1989 Journal of the IIC-Canadian Group.

Permanent inks. The inks in pens on the market were recently tested for permanence in separate projects by the land State Archives, the U.S. National Archives, and the Glasgow Art Gallery. Reports naming the pens containing the most permanent inks were published in 1989-90. This might seem to give conscientious record-keepers all the information the need, but such lists of products are not as useful as they seem. Manufacturers' formulas change without notice, and products are frequently withdrawn from the market or made available only in selected locations. The situation is well summarized in the UNESCO publication, "Survey on National Standards on Paper and Ink to be Used by the Administration for Records Creation: A RAMP Study with Guidelines." It says that technology of production has rim ahead of standards,. and the best way to cope is to follow Sweden's example and have a standard reference ink. Any ink used should be at least as resistant as the reference ink to daylight, air, water and alcohol.

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