Mass deacidification

Last updated

Mass deacidification is a term used in library and information science as one possible measure against the degradation of paper in old books, the so-called "slow fires". The goal of the process is to increase the pH of acidic paper. Although acid-free paper has become more common, a large body of acidic paper still exists in books made after the 1850s; this is because of its cheaper and simpler production methods. Acidic paper, especially when exposed to light, air pollution, or high relative humidity, yellows and becomes brittle over time. [1] During mass deacidification an alkaline agent is deposited in the paper to neutralize existing acid and prevent further decay. [2] Mass deacidification is intended for objects on acidic paper that will be lost if no action is performed.

Contents

History of research and process development

Mass deacidification—along with microfilm and lamination—was developed during the early and mid-20th century as a response to the chemical process of hydrolysis by which the fibers that constitute paper, providing its structure and strength, have their bonds broken, resulting in paper that becomes increasingly brittle over time. Environmental pollutants can react with paper to form acids that promote oxidation, creating more acid as a by-product, which results in a positive feedback loop of autocatalytic destruction. [3] Supported in part by grants from the Council on Library Resources, William J. Barrow conducted research into paper decay and found that no more than three percent of books published between 1900 and 1949 would survive more than fifty years. In response to this, a Standing Committee on the Preservation of Research Library Materials was formed by the Association of Research Libraries (ARL) in 1960. [4]

Barrow also invented an aqueous process to neutralize acid in paper while depositing an alkaline buffer that would slow the rate of decay. [5] In addition to Barrow's original method, both non-aqueous—employing organic solvents—and vaporous—the Library of Congress' DEZ (diethyl zinc) treatment—methods of achieving the same results have been researched in an attempt to reduce time, labor, and cost requirements. [6]

One technique proposed is to place books in an evacuated chamber, then introduce diethylzinc (DEZ). In theory, the diethylzinc would react with acidic residues in the paper, leaving an alkaline residue that would protect the paper against further degradation. [7] In practice, the heating required to remove trace water from the books before reaction (DEZ reacts violently with water) caused an accelerated degradation of the paper, a series of chemical reactions between DEZ and other components of the book (glues, bindings), caused further damage, and produced unpleasant aromas. In the 1980s, a pilot plant for mass deacidification, using this process, was constructed by NASA and was tested on books provided by the Library of Congress. [8] In 1986 it was discovered that the DEZ had not been removed in one of the deacidification runs and pooled in the bottom of the chamber, possibly remaining within the plumbing. DEZ is violently flammable when it comes in contact with either oxygen or water vapor, so the vacuum chamber could not be opened to remove the books within. Eventually, explosives were used to rupture the suspect plumbing; suspicions of the presence of residual DEZ were confirmed by the subsequent fire that destroyed the plant. In his book Double Fold , Nicholson Baker discusses the failure of the NASA program at great length.

The chemical company AkzoNobel made later attempts at refining the process. The risks of fire and explosions were reduced by a better process design, however, damage and odors remained a problem. In the end, AkzoNobel determined the process was not a viable commercial proposition and shut down their research at the end of 1994.

Goals

These are the results that the Library of Congress expected of an ideal mass deacidification treatment in 1994:

Faculty members of the Slovak University of Technology added these further requirements:

Effects

All of the processes imparted an adequately high pH in studies conducted by the European Commission on Preservation and Access, the Library of Congress, and a team of scientists from the Centre de Recherches sur la Conservation des Documents Graphiques in the early and mid-nineties. BookKeeper produced a pH of 9–10. [9] CSC Book Saver yielded a pH of 8.78–10.5. [11] Wei T'o gives 7.5 to 10.4, [12] and Papersave gives a pH of 7.5–9. [13]

The same studies also found that the processes had adverse cosmetic side effects. BookKeeper left "a palpable residue", clamp marks on the covers, and caused some of the colored inks to rub off. [9] CSC Book Saver left a "white powdery deposit" on books. [14] Papersave caused "discoloration, white deposit, Newton's rings, bleeding of inks and dyes, odor and different 'feel' of the paper." [15] Wei T'o caused "odor, white residues, rings, cockling, (yellow) discolorations and adhesive bleeding." [16]

Conservators from the British Library acknowledge that the existing mass deacidification processes are still being developed and further research needs to be conducted on their chemical and mechanical effects. [17]

Services

Several commercial deacidification techniques are on the market as of 2008:

BookKeeper, CSC Booksaver, Papersave, and Wei T'o are also available as hand-held sprays.

Adoption and costs

While deacidification has been adopted by major research libraries such as the Library of Congress and the New York Public Library, it is not clear whether many archives, particularly those in the United States, have followed suit. Some European national archives have tested deacidification techniques. The United States' National Archives and Records Administration (NARA), which pioneered an aqueous technique that improved upon Barrow's, chose to invest its preservation dollars elsewhere. [5] In 2000, the Chief of the NARA Document Conservation Laboratory defended the lack of a mass deacidification program by pointing to differences between library and archival collections. For example, noting that many of the papers coming to NARA were of a higher quality than those in library collections; that the Archives does not receive records from federal government agencies until they are at least 30 years old, by which time acidic paper will have already been irrevocably weakened, and that limited resources might best be applied elsewhere, such as climate control. Under the Archives' Twenty-Year Preservation Plan, emphasis was placed on achieving the "maximum benefit for the greatest number of records." [25]

Though now dated, several sources estimate the costs and suitability of deacidification treatment. Studies conducted by the Harry Ransom Humanities Research Center and the General State Archive of the Netherlands found the DEZ method might be particularly applicable to archival materials. [26] It was estimated that deacidification costs, excluding transportation and handling, during the early 1990s was $5–10 per volume. [27] During 1995–1997, the Library of Congress received $2 million in appropriations to deacidify 72,000 books using the Bookkeeper commercial method and evaluate alternative methods. The actual cost per book was $11.70. [28] Finally, a recent cost comparison with reformatting options per volume yielded $125 for microfilming, $50 for scanning and minimal indexing and, based on a New York Public Library project, $16.20 for deacidification. [6]

As of 2022, there were five mass deacidification plants in the world. [29]

See also

Related Research Articles

<span class="mw-page-title-main">Slow fire</span> Paper embrittlement of a book or document

A slow fire is a term used in library and information science to describe paper embrittlement resulting from acid decay. The term is taken from the title of Terry Sanders's 1987 film Slow Fires: On the preservation of the human record.

<span class="mw-page-title-main">Magnesium oxide</span> Chemical compound naturally occurring as periclase

Magnesium oxide (MgO), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of MgO and consists of a lattice of Mg2+ ions and O2− ions held together by ionic bonding. Magnesium hydroxide forms in the presence of water (MgO + H2O → Mg(OH)2), but it can be reversed by heating it to remove moisture.

<span class="mw-page-title-main">Digitization</span> Converting information into digital form

Digitization is the process of converting information into a digital format. The result is the representation of an object, image, sound, document, or signal obtained by generating a series of numbers that describe a discrete set of points or samples. The result is called digital representation or, more specifically, a digital image, for the object, and digital form, for the signal. In modern practice, the digitized data is in the form of binary numbers, which facilitates processing by digital computers and other operations, but digitizing simply means "the conversion of analog source material into a numerical format"; the decimal or any other number system can be used instead.

Sizing or size is a substance that is applied to, or incorporated into, other materials—especially papers and textiles—to act as a protective filler or glaze. Sizing is used in papermaking and textile manufacturing to change the absorption and wear characteristics of those materials.

<span class="mw-page-title-main">Foxing</span> Age-related process of deterioration occurring on paper products

Foxing is an age-related process of deterioration that causes spots and browning on old paper documents such as books, postage stamps, old paper money and certificates. The name may derive from the fox-like reddish-brown color of the stains, or the rust chemical ferric oxide which may be involved. Paper so affected is said to be "foxed".

<span class="mw-page-title-main">Acid-free paper</span> Type of paper used for preservation

Acid-free paper is paper that, if infused in water, yields a neutral or basic pH. It can be made from any cellulose fiber as long as the active acid pulp is eliminated during processing. It is also lignin- and sulfur-free. Acid-free paper addresses the problem of preserving documents and preserving artwork for long periods.

Preservation of documents, pictures, recordings, digital content, etc., is a major aspect of archival science. It is also an important consideration for people who are creating time capsules, family history, historical documents, scrapbooks and family trees. Common storage media are not permanent, and there are few reliable methods of preserving documents and pictures for the future.

<span class="mw-page-title-main">Accelerated aging</span> Product testing method

Accelerated aging is testing that uses aggravated conditions of heat, humidity, oxygen, sunlight, vibration, etc. to speed up the normal aging processes of items. It is used to help determine the long-term effects of expected levels of stress within a shorter time, usually in a laboratory by controlled standard test methods. It is used to estimate the useful lifespan of a product or its shelf life when actual lifespan data is unavailable. This occurs with products that have not existed long enough to have gone through their useful lifespan: for example, a new type of car engine or a new polymer for replacement joints.

<span class="mw-page-title-main">Diethylzinc</span> Chemical compound

Diethylzinc (C2H5)2Zn, or DEZ, is a highly pyrophoric and reactive organozinc compound consisting of a zinc center bound to two ethyl groups. This colourless liquid is an important reagent in organic chemistry. It is available commercially as a solution in hexanes, heptane, or toluene, or as a pure liquid.

<span class="mw-page-title-main">Preservation (library and archive)</span> Set of activities aimed at prolonging the life of a record or object

In conservation, library and archival science, preservation is a set of preventive conservation activities aimed at prolonging the life of a record, book, or object while making as few changes as possible. Preservation activities vary widely and may include monitoring the condition of items, maintaining the temperature and humidity in collection storage areas, writing a plan in case of emergencies, digitizing items, writing relevant metadata, and increasing accessibility. Preservation, in this definition, is practiced in a library or an archive by a conservator, librarian, archivist, or other professional when they perceive a collection or record is in need of maintenance.

The Brittle Books Program is an initiative carried out by the National Endowment for the Humanities at the request of the United States Congress. The initiative began officially between 1988 and 1989 with the intention to involve the eventual microfilming of over 3 million endangered volumes.

<i>Double Fold</i> 2000 non-fiction book by Nicholson Baker

Double Fold: Libraries and the Assault on Paper is a non-fiction book by Nicholson Baker that was published in April 2001. An excerpt appeared in the July 24, 2000 issue of The New Yorker, under the title "Deadline: The Author's Desperate Bid to Save America's Past". This exhaustively researched work details Baker's quest to uncover the fate of thousands of books and newspapers that were replaced and often destroyed during the microfilming boom of the 1980s and 1990s. Double Fold is a controversial work and is not meant to be objective. In the preface, Baker says, "This isn't an impartial piece of reporting", and The New York Times characterized the book as a "blistering and thoroughly idiosyncratic attack".

William James Barrow was an American chemist and paper conservator, and a pioneer of library and archives conservation. He introduced the field of conservation to paper deacidification through alkalization.

Preservation of meaning in library, archival or museum collections involves understanding spiritual, ritual, or cultural perceptions of value for specific objects, and ensuring these values are maintained and respected. Meaning is something assigned to objects of cultural or spiritual significance based on interpretations and perceived values by user populations, a process known as social construction of an object. When moved to memory institutions such as libraries or museums, these objects of social construction require unique approaches to preservation and maintenance in order to remain relevant as representations of cultural or spiritual societies.

Preservation survey is the process of collecting and analyzing data about the physical condition of library materials.

<span class="mw-page-title-main">Paper</span> Material for writing, printing, etc.

Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses, or other vegetable sources in water, draining the water through a fine mesh leaving the fibre evenly distributed on the surface, followed by pressing and drying. Although paper was originally made in single sheets by hand, almost all is now made on large machines—some making reels 10 metres wide, running at 2,000 metres per minute and up to 600,000 tonnes a year. It is a versatile material with many uses, including printing, painting, graphics, signage, design, packaging, decorating, writing, and cleaning. It may also be used as filter paper, wallpaper, book endpaper, conservation paper, laminated worktops, toilet tissue, currency, and security paper, or in a number of industrial and construction processes.

Inherent vice is the tendency in physical objects to deteriorate because of the fundamental instability of the components of which they are made, as opposed to deterioration caused by external forces. All objects have some kind of inherent vice as a result of the baseline law of entropy.

<span class="mw-page-title-main">Conservation and restoration of books, manuscripts, documents, and ephemera</span> Activity to extend the life of historical materials

The conservation and restoration of books, manuscripts, documents, and ephemera is an activity dedicated to extending the life of items of historical and personal value made primarily from paper, parchment, and leather. When applied to cultural heritage, conservation activities are generally undertaken by a conservator. The primary goal of conservation is to extend the lifespan of the object as well as maintaining its integrity by keeping all additions reversible. Conservation of books and paper involves techniques of bookbinding, restoration, paper chemistry, and other material technologies including preservation and archival techniques.

Helen Diana Burgess, was a Canadian conservation scientist. Burgess spent her career at the Canadian Conservation Institute ("CCI"), where she was a Senior Conservation Scientist. She was a researcher in paper and textiles conservation processes and an expert in the areas of cellulose degradation analysis, conservation bleaching, washing, enzyme applications on paper, as well as aqueous and mass deacidification of paper.

Acidic paper is paper that had some acidic substances used during the manufacture process. This type of paper, widely used since the mid-nineteenth century, turns yellow in a short time and becomes extremely brittle, which causes huge losses in library and archives collections.

References

  1. Cheradame, H et al. (2003). Mass Deacidification of paper and books: I: study of the limitations of the gas phase process. Restaurator: International Journal for the Preservation of Library and Archival Material, 24, 227.
  2. Lienardy, A. & Van Damme, P. (1990). Practical Deacidification, Restaurator: International Journal for the Preservation of Library and Archival Material, 11,2.
  3. Library of Congress. (1994). An evaluation of the BookKeeper mass deacidification process: Technical Evaluation Team Report for the Preservation Directorate, Library of Congress, Appendix E.
  4. Marcum, D. & Friedlander, D. (2003). Keepers of the Crumbling Culture: What Digital Preservation Can Learn from Library History. URL accessed April 28, 2008.
  5. 1 2 Ritzenthaler, M. (1993). Preserving Archives and Manuscripts
  6. 1 2 Pillete, R. (2003). Mass Deacidification: A Preservation Option for Libraries World Library and Information Congress: 69th IFLA General Conference and Council. URL accessed April 28, 2008.
  7. Porck, H. (1996). Mass deacidification. An update of possibilities and limitations. DEZ Archived 2008-03-11 at the Wayback Machine . URL accessed December 2, 2007.
  8. Harris, K. & Shahani, C. (1994) Library of Congress. Preservation. Mass deacidification: An initiative to refine the diethyl zinc process URL accessed December 1, 2007.
  9. 1 2 3 Library of Congress. (1994). URL accessed April 5th,2022.
  10. Cedzova, M. et al. (2006). Patents for Paper Deacidification. Restaurator: International Journal for the Preservation of Library and Archival Material,27, 36.
  11. Dupont, A. et al. (2002). Testing CSC Book Saver, a commercial deacidification process. Restaurator: International Journal for the Preservation of Library and Archival Material,23, 40.
  12. Brandis, L. (1994). Summary and evaluation of the testing sponsored by the Library of Congress of books deacidified by the FMC, AKSO, and Wei T'o mass deacidification process. Restaurator: International Journal for the Preservation of Library and Archival Material,15, 112.
  13. Wittekind, J. (1994). The Battelle mass deacidification process: A New method for deacidifying books and archival materials. Restaurator: International Journal for the Preservation of Library and Archival Material,15, 195.
  14. Dupont, A. et al. (2002). Testing CSC Book Saver, a commercial deacidification process. Restaurator: International Journal for the Preservation of Library and Archival Material,23, 45.
  15. Porck, H. (1996). Mass deacidification. An update of possibilities and limitations. Battelle Archived 2008-03-11 at the Wayback Machine . URL accessed December 1, 2007.
  16. 1 2 Porck, H. (1996). Mass deacidification. An update of possibilities and limitations. Wei T'o and Sable Archived 2006-07-19 at the Wayback Machine . URL accessed October 5, 2007.
  17. Knight, B. (2004). A Conservation research strategy for the British Library Archived 2011-05-21 at the Wayback Machine . pg. 4. URL accessed December 1, 2007.
  18. Porck, H. (1996). Mass deacidification. An update of possibilities and limitations. BookKeeper Archived 2006-07-19 at the Wayback Machine . URL accessed December 1, 2007.
  19. "PTLP: Home" . Retrieved 2008-06-07.
  20. 1 2 Banik, G. (2003). Mass deacidification technology in Germany and its Quality Control. Restaurator: International Journal for the Preservation of Library and Archival Material,26, 64.
  21. "CSC" . Retrieved 2008-06-07.
  22. http://www.nitrochemie.com/pdfdoc/papersave/papersave-swiss-brosch_en.pdf%5B%5D
  23. Anders, Manfred. "Mass Deacidification — Conservation for Libraries, Archives und Museums — ZFB GmbH Leipzig — Massenentsäuerung". Archived from the original on 2007-10-26. Retrieved 2008-06-07.
  24. "Wei T'o Index — Cover Page". Archived from the original on 2019-01-10. Retrieved 2008-06-07.
  25. Jones, N. (2000). Mass Deacidification: Considerations for Archives National Archives and Records Administration 15th Annual Preservation Conference. Washington, D.C., March 2000, URL accessed April 28, 2008.
  26. Harris, K. & Shahani, C. (1994). Mass Deacidification: An Initiative to Refine the Diethyl Zinc Process
  27. Sparks, Peter G. (1990). Technical Considerations in Choosing Mass Deacidification Processes. URL accessed April 28, 2008.
  28. Dalrymple, W. (1997). A Paper Chase: Technology Helps Library Save its Paper Collections. LC Information Bulletin. URL accessed April 28, 2008.
  29. "Qatar National Library Inaugurates its First Mass Deacidification Plant in the Middle East | Qatar National Library".