Back to 2. General Preservation Factors
Up to Table of Contents
Ahead to 4. Photographic Materials

3. Paper and Other Traditional Materials

This group, with the greatest diversity, contains the oldest materials. They are accessible with the naked eye and the majority are made of materials which have the capacity to last for a long time if cared for correctly. Many of the standards cover a range of materials, and include details of the best storage conditions.

The options for preservation range from appropriate stable environmental conditions, through boxing and packing, copying on to some other medium, to conservation. The latter is the most expensive solution and can only be afforded for a small number of items of particular importance. Each institution or organisation will have to make its own list of priorities and decide how best to afford appropriate protection to every category of material. Basic protection, such as good housekeeping, training staff to handle items with care, or storing them on shelving rather than the floor does not cost much money and should be part of every programme for preservation.

Microfilms can provide both an access copy of original documents and also a safeguard against loss through decay or disaster. If high fidelity microfilms are made, they can also be used as the source for making digital copies.

Paper

Both Oriental and Western papers are made using cellulose (vegetable fibre or materials made from such fibres such as rags) and water, the former being beaten into a pulp, dispersed in water and then drained through a tight mesh mould. Once the water has drained away, the film of pulp remaining on the mould is transferred to felts, dried and pressed to produce a sheet of paper which may require further treatment depending on the proposed use. While the original ingredients were relatively pure the paper maintained good strength and longevity. However, the introduction of wood pulp in the nineteenth century to satisfy the increasing demand for paper led to a deterioration in quality. Additives in the shape of alum, or alum rosin, chlorine, sulphate of soda or other chemicals designed to speed the production of the paper, or counteract the natural acidity of the wood, caused more damage by breaking down the fibres which in consequence embrittled the paper.

The reasons for the decay of nineteenth and twentieth century papers are well known, but until recently few solutions have been proffered. The adoption of rigorous standards in the manufacture of paper intended for long term use is the solution for the future survival of paper documents but does nothing for those which already exist. Good storage, which includes boxing archive and library material whenever possible, maintaining stable environmental conditions, excluding light, keeping the store rooms clean and dry and handling the material carefully contribute to the overall preservation of these materials. The range of temperature and relative humidity will vary according to the area of the world but it is particularly important not to exceed 65% relative humidity, the point at which mould growth is triggered. Specialist conservation work, which involves treatment of the material, should be left to trained conservators who will be able to assess the problems of individual items. Mass de-acidification is used in some archives and libraries but is not practised universally and is expensive. Some modern papers used for copying or faxing are coated and retain the text for a very short time only. These should be copied as soon as possible using good quality paper.

Parchment

Parchment is made from the skin of an animal, usually sheep but calf skin is also used. It consists of collagen fibres, arranged in three dimensional bundles, which are themselves proteins composed of long chain amino acids. The skin is turned into parchment during a long process which involves the removal of the fur and flesh with the use of lime, scraping the skin, stretching it on frames to dry under tension, polishing it and finally rubbing it with French chalk to provide a good writing surface. It was the most common writing medium of the Middle Ages in Europe, superseding papyrus by the third or fourth century AD, until the invention of printing in the fifteenth century increased the demand for a lighter, more flexible medium.

It is a very tough and versatile material which, due to its nature, is hygroscopic. It reacts to external temperature and humidity which must, therefore, be kept as stable as possible. Excess relative humidity endangers the parchment from both mould growth and deterioration but, by contrast, if the parchment is too dry, the ink is likely to flake off. The ink is also susceptible to being abraded by rough handling or tensions induced by unstable environmental conditions. The range of conditions for the survival of parchment are similar to those required for paper.

Palm Leaves and Birch Bark

These materials are cellulose based, being vegetable fibre. As natural materials, without the processing involved in paper making, they are quite hard wearing but are susceptible to cracking. The inks used are frequently carbon based and may be endangered by incorrect storage, environmental conditions or handling. The standards for these are similar to those for paper and parchment

Standards

ISO NP 11799

Storage requirements for archive and library materials

ISO WD 11108

Archival paper ­ requirements for permanence and durability

ISO/TC46

SC10


Storage requirements for library and archival materials

ISO/TC46

SC10


Requirements for binding of books, periodicals, serials and other paper documents for archive and library use. Methods and materials

ISO DIS 11800

Information and documentation - Requirements for binding materials and methods used in the manufacture of books.

ISO CD 14416

Information and documentation - Requirements for binding of books, periodicals, serials and other paper documents for archive and library use - Methods and materials

Reference Literature

Dureau, JN and Clements, DNG

Principles for the preservation and conservation of library materials

IFLA Professional report no 8 1986

Preservation of Historical Records

Committee on Preservation of Historical Records, of the National Research Council of the National Academy of Sciences. National Academy Press, 1985

Ellis, J

Keeping Archives

Thorpe and Australian Society of Archivists; 1993

Favier, J, Neirinck, D

La Pratique Archivistique Francaise

Paris, Archives Nationales, 1993

Ritzenthaler, ML

Archives and manuscripts

Society of American Archivists, 1993

UNESCO RAMP studies in general. Available in Arabic, Chinese, English, French, Russian and Spanish.

Also see the publications of the Commission on Preservation and Access (Washington D.C. USA) and the European Commission on Preservation and Access (The Hague, The Netherlands).

Back to 2. General Preservation Factors
Up to Table of Contents
Ahead to 4. Photographic Materials