Preserving Paper

Eugene Baby

 

The material used in the paper-making process determines the stability and lifespan of the product and is the most important thing to consider as a preservationist or family archivist.

Some materials are very stable and will remain intact for centuries. Other materials deteriorate quickly and need to be replaced as soon as possible. Early paper production used linen, cotton and hemp. These materials are relatively stable and durable and will last a long time. As paper production increased during the 19th century, a shortage of
img011-1990-Andrade (Harkness) Casey-Sportslinen, cotton and hemp occurred which caused papermakers to look for raw materials that were cheaper and easier to work with. In the 1840s groundwood pulp began to be used. This is a form of wood that has not been cooked or chemically treated, and has a high lignin content and is very acidic.[1]

Acid is the single most common cause for the accelerated rate of deterioration in paper.

Most commonly, newspapers use this cheap form of paper, which is why they yellow and brown more quickly than other types of paper. When acid is exposed to light, heat and humidity, it yellows and browns and weakens the paper causing it to become brittle and to break off. Paper made with inferior materials are said to have “inherent vice.” The term inherent vice refers to deterioration that is caused as a result of the materials that make an item, in this case paper, as opposed to outside influences that cause paper to deteriorate such as high humidity, water, or light.[2] The “vice” is inherent in (inside) the product.

Sizing materials used in the manufacturing process are another source that causes poor paper quality. In particular alum-rosin sizing agent, which began to be used in the United States in the 1850s, needs an acidic environment to be produced. Alum-rosin leaves a sulfuric acid by-product that causes brittle paper that browns and deteriorates quickly. Later in the century, in the 1870s, a machine process for making alum-rosin sizing resulted in even higher acidic content further accelerating “brittle book syndrome.”

POOR QUALITY PAPER NOT ONLY DETERORATES MORE QUICKLY, IT ALSO CONTAMINATES ANY MATERIALS IT COMES IN CONTACT WITH.

As early as 1898 the Committee on the Deterioration of Paper in London was formed as a result of librarians’ concern over the deterioration of books in their charge.

IMG_1535By the 1930s it was well known that acid was at the root of the problem causing brittle, browned and yellowed books in large library collections. At this time the search for “permanent paper” began.   Permanent paper as defined by preservationists is: “Paper which during long term storage in libraries, archives and other protected environments will undergo little or no change in properties that affect use.”[3] Not until 1984 was the first ANSI standard for permanent paper issued.

Today the cheap copy/printing paper we use in our printers and copy machines passes ANSI standards.

Librarians and archivists routinely copy old deteriorating paper onto the current acid-free paper. As an archivist I have spent many an hour at the copy machine doing just this. As a family historian, you may do the same.

Acid free paper has a PH of 7 or higher.  Acid free paper made with alpha cellulose stock will have little or no lignin.

Buffered paper has an alkaline reserve, or buffering agent added druing production to lower the PH level.  Calcium carbonate or magnesium carbonate are the most common buffering agents.

 

[1] http://dictionary.reference.com/browse/groundwood-pulp 2-2-16
[2] https://preservationhistory.wikispaces.com/Brittle+Paper 2-2-16
[3] https://preservationhistory.wikispaces.com/Brittle+Paper 2-2-16

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