BRITTLE PAPER
by
Rebecca Fitzgerald, Archivist
2001
Until the early nineteenth century, paper was made by hand from cotton rags, which were free from impurities and had long, supple fibers. The sizing used to fix print was made from animal gelatin, which was chemically inert. That is why books and manuscripts produced before this time are frequently white, supple, and long-lasting. However, the industrial revolution changed the way paper was made. Manufacturing by machine replaced hand techniques, and the resultant powerful bashing increased the stress on the fibers and caused them to break down and become shortened. Further, because of the poverty and upheaval resulting from the industrial revolution, rags became scarce and declined in quality. Clothes were reused, resewn, dyed, and frequently mended, and chlorine had to be added to the process to whiten the rags. Sizing was added to the pulp rather than at the end of the process, and alum rosin was substituted for animal gelatin. The chlorine and alum produced hydrochloric and sulfuric acid. Finally, paper manufacturers had to turn to wood pulp in the middle of the nineteenth century, when the supply of rags could not meet the surge in demand for paper. This added lignins and tannins to the mix.
Inherent vice is something in the composition of an item that causes its own deterioration and destruction, and does not arise from any external factors. Modern papermaking, which involves converting raw wood to paper, thus creates a product in which inherent vice is added at nearly every step on the way. Logs are pulverized into pulp, bleached, coated with sizing, and pressed, with acids and other impurities added to short, unstable fibers. Acids weaken the molecular bonds of cellulose fibers, resulting in the familiar yellowing and embrittlement of paper. It is estimated that about 80 million books in North American research libraries were printed on acidic paper.
Inherent vice is not the only threat to paper, which is also subject to chemical, physical, biological, and man-made dangers. Paper readily reacts with chemicals in the air or in the medium against which it lies, such as oxygen, carbon dioxide, and salts. Physical threats include sunlight, heat, humidity, pollutants, and other abrasives. Sunlight hastens yellowing, and excessive heat and humidity, or wide and frequent swings, create an opportunity for more chemical reactions to occur, and cause the breakdown of the bonds holding the fibers together. Biological threats include algae, bacteria, and fungi. Pests and insects eat paper, and contaminate it with their trackings and droppings. People mistreat and abuse books and paper with improper handling and storage, and outright destruction. Even paper of the highest quality will deteriorate and become embrittled over time if exposed to these hazards.
Alkaline paper, with a pH over 7, was accidentally made early in the twentieth century when carbonates were used to eliminate something called lime mud. In the 1950s, B.W. Wilson Paper Company and Barrow Research Lab in Richmond, VA, perfected a method to make alkaline, or acid-free, paper from wood fibers. They started out with wood having long cellulose fibers, and eliminated unwanted residual chemicals from the cooking and bleaching processes. The most significant improvement resulted from the substitution of chemically stable synthetic resin for alum rosin sizing, which reduced acidity and impurities. Acid-inhibiting carbonates were used as filters, and the finished product had the same quality as hand-made paper.
Not only did this process produce better and longer-lived paper, it also reduced manufacturing costs. Energy consumption was reduced due to shorter refining and drying times. The operation was cleaner, and the chemicals used were more stable and less destructive to the equipment and environment. This process also gave off much less waste. The calcium carbonate used as a filler was cheaper than fiber.
If manufacturing acid-free paper is cheaper, cleaner, and produces a better product, why haven’t all the paper making companies jumped on the bandwagon? Despite a law signed in 1990 urging the use of acid-free paper for publication of important government documents, the use of acid-free paper has not become general. It is available, but not promoted. I can order acid-free paper from my supplier, but I only have one choice, not the myriad options I would be given if I were ordering paper of lesser quality. Although I get a discount, I do not get the special SPECIAL discount for ordering the paper promoted by the supplier.
There are two reasons for this. It is costly and time-consuming to shut down manufacturing plants to retool and, unless carefully planned, could result in a loss of business if something goes wrong. Further, there is no strong demand to make it worthwhile for companies to undertake a major expense of this nature. The International Paper Company graciously sent me a free promotional video describing the papermaking process. It is immediately clear that they are defensive about only two issues: reforestation and environmental protection. The video did not once mention acid-free paper. And, indeed, there is no reason that it should. Archivists and records managers do not have anything like the clout of the environmental lobby. Since I can’t visualize records professionals chaining themselves to boxes of acidic paper or forming human chains in front of paper plants, we will probably have to wait for a law to be passed, for major paper purchasers to refuse to buy acidic paper, or for someone like Nicholas Baker to galvanize the community.
In the meantime, what options are available to the archivist, rare books librarian, or records manager? The quality of most of the paper manufactured in the United States today is very good, and should last 50 years. Fortunately for records managers, this is well over the retention period for most records. But what can be done with the paper that holds the information with enduring value, or with the paper now in records centers and archives that is yellow, brittle, and crumbling?
One old saying holds sway here: an ounce of prevention is worth a pound of cure. The ideal conditions for the storage of paper is about 65 degrees Fahrenheit and 45 to 55 percent humidity. The higher the temperature, the greater the molecular activity, and the faster the bonds holding paper together break down. With high humidity, more water molecules are available to be absorbed by paper, which both hastens its breakdown and provides a congenial habitat for mold. A very dry environment is also destructive to the bonds holding paper fibers together. There is evidence that frequent swings in temperature and/or humidity cause more damage than high but steady readings. Boxing creates a micro-climate and provides some protection against swings in temperature and humidity, as well as a partial barrier to dust, dirt, and pollutants.
Paper records should also be protected against fire, and stored in a secure area where access is limited. Non-caustic chemicals should be used for cleaning the area. Insect traps should be set at intervals in the storage area and regularly monitored. Once evidence of the presence of pests is discovered, the least harmful effective means for eradicating them should be undertaken. Poison should never be used for rodents, because their bodies may be unrecoverable and will attract other pests.
There are five options for reformatting for preservation: photocopying, papersplitting, microfilming, mass deacidification, and digitization. Selecting which option is most appropriate for your needs involves consideration of costs, access required, length of retention, user needs, skills of staff and their availability, reliability of product, pre- and post-treatment necessary, and analysis of equipment needed. And each project, even the simplest, must be carefully planned beforehand.
Papersplitting is a complicated technique developed by the Europeans to lift each side of the paper and join them back together with a piece of Japanese paper in between. This process costs hundreds to thousands of dollars for each item, and is reserved only for the most valuable and revered objects, such as medieval manuscripts or founding documents.
Preservation photocopying is used by many librarians and archivists to replace deteriorating items. They use acid-free, buffered bond paper with carbon-based toner. Great care must be taken to ensure that the toner adheres properly to the paper and that all the information has been copied and is legible. It is estimated that this paper should last 500 years. This option is very user-friendly, but does not result in any space savings. If done properly, costs are estimated at slightly under $75 for 300 pages, or about a fourth of a records center carton.
Microfilming has been readily available since the 1920s. The current controversy raised by Nicholas Baker illustrates all its advantages and disadvantages. It is a static technology with reliable output if done correctly, is easily copied and disseminated for access, provides tremendous space savings, and is human readable. However, microfilming requires a great deal of prep work: records must be processed so that they are in some kind of searchable order, all bindings must be removed, and the product must be carefully checked to ensure its reliability. Even the smallest lapse in quality is final: if even one page is illegible, and the originals have been discarded, the result is a loss of information. Microfilm made with silver halide is projected to last 500 years, if stored in a vault under proper environmental conditions, but no one yet knows if this is true. It must be inspected regularly. Microfilm is also not user friendly and requires the use of special equipment. Microfilming oversized, color, and continuous-tone items may also pose insuperable problems. Costs are estimated at $75 for 300 pages.
Mass deacidification is another option that has recently become viable. Early efforts ultimately proved unsatisfactory. Facilities using DEZ (diethyl zinc) tended to explode, while the solution marketed under the name Wei T’o used solvents that were unstable and not environmentally friendly. However, a company called Bookkeeper has developed a process using magnesium oxide and an inert liquid that seems safe for all kinds of materials, including leather. No pre-treatment or post-treatment is necessary. Materials that are already fragile and embrittled are not candidates for this treatment, because the items are immersed in vat, and are shaken vigorously so that every surface is coated. Currently, the technique is used primarily for books, although a spray is available. The cost is about $16 to $18 for 300 pages. It will not restore paper to its original state, but will greatly delay further deterioration. It is also safe for users and the environment.
Digitization has many advantages: greater access, fidelity of copies, tremendous space savings if the originals are discarded. However, it requires a huge investment of time and staff if it is to be done correctly. Planning must be very detailed and careful, and metadata must be captured before, during, and after to track items and provide access to their contents. Site visits to institutions which have already undertaken digitization projects are a necessity to learn both from their mistakes and their successes. Your organization must be fully committed to the project, because costs for equipment and staff are going to be high, and the data will have to be migrated as technology changes. Responsible strategies for migration will also have to be decided upon and committed to, in order to minimize the inevitable loss of data. For items with retention dates of less than 10 years, digitization is a viable choice, but for records with longer or permanent retention, this option is problematic.