Preserving Family Photos and Documents - Archival Paper Basics

Understanding the basic archival qualities of paper is useful in understanding how long a family photo or document might last, and to better select proper paper storage products.

Most paper produced since the late 1800s has been produced using wood pulp, an inherently acidic material. The quality of paper made from wood pulp often equates to how many steps are taken in the manufacturing process to reduce the acidity of the paper and to improve the chemical stability of better quality papers.

This is why we see rapid deterioration of cheaper paper materials such as newsprint, which remains highly acidic. This rapid deterioration is the result of chemical reactions, which are accelerated by light, heat, and humidity.

There are some labeling terms often used with paper products, which provide clues to the appropriateness of using paper for archival storage purposes.

Be cautious as you see these terms, as suppliers' definitions of archival qualities vary. In any case, if you can become satisfied that paper being used for reproductions and storage are chemically stable, your preservation efforts are improved.

pH Balanced - A chemically neutral paper is typically described as pH balanced. This paper will have a pH between 7.5 and 10. A pH of 7.5 is often referred to as "balanced" and a pH of 10 is often associated with "archival".

Buffered - Paper is referred to as buffered when it is manufactured to contain a small amount of Calcium Carbonate to act as a barrier to acid contamination. The calcium carbonate is typically in the range of 2%.

Acid Free - The term acid free is used to suggest a very low acidic content. In paper content descriptions, this is often denoted as the % of lignin content. Lignin is an acidic compound present in wood. Therefore, a very low lignin content percentage is indicative of a low acid content, and is often described as acid free.

Archival - Materials are best described as archival when the pH approaches 10, and lignin is not present. However, you may see materials described as archival when pH is above 7.5, only small percentages of lignin are present, and materials are buffered.

Although many products sold through mass marketers are labeled archival or such, the best way to be certain of labeling is to buy from sources that are experienced with these materials. Dick Blick Art Materials has a dedicated archival materials department and Archival Methods provides a broad range of archival storage products, and provides custom solutions as well.