Acid-Free Paper: It Keeps Going and Going

The material your photos are printed on matters. Check out how acid-free paper helps keep images looking fresh longer.

Photographs yellowing, paperbacks becoming brittle, old newspapers breaking down—all these are visible signs of the need for acid-free paper. But they take time to appear. Despite the fact that wide-scale printing has been around for centuries, it was only in the 1930s that archivists brought attention to the acid-caused breakdown of printed materials. It wasn’t that paper had just stayed intact or lied about its birthday until then—instead, modern papers and printing materials were decomposing more rapidly than older ones.

The culprit lay in the molecular backbone of paper: cellulose, a compound common to all green plants, including the trees, cotton, and flax from which most paper is made. The combination of atmospheric moisture and acidity—whether stemming from pollution or chemical impurities in the paper itself—causes cellulose chains to break down. Whereas older paper was typically made from materials with long cellulose fibers, such as cotton and linen rags, modern papers such as newsprint and the pages of mass-market paperbacks are made from ground wood pulp, whose cellulose fibers are much shorter and, consequently, less resistant to acid.

Using acid-free paper for photographic prints, framing, or scrapbooking doesn’t guarantee that they’ll never decay or spontaneously combust, but it does extend their lifespan considerably. Consumers can look to alkaline paper—the gold standard acid-free product—or simply seek out paper materials labelled as “archival” or “conservation quality.”