Glossary Term: Acid Free Paper

Acid-free paper is paper that if infused in water yields a neutral or basic pH (7 or slightly greater). I get rid of “slightly”. It can be made from any cellulose fiber as long as the active acid pulp is eliminated during processing. I would say, “As long as the acidic lignin (binding agent in the pulp) is neutralized” It is also lignin- and sulfur-free. I would get rid of “also” and say “The resulting paper is lignin and sulfur free, and usually contains a buffering agent such as Calcium Carbonate” to boost alkalinity. Cotton papers (rag) made from cotton fibers, naturally do not contain these acids, and thus have a superior shelf life (and cost).

If an acidic product comes into contact with paper, photos, textiles or other similar items, the acid can migrate, causing permanent damage and decay. This is why it is so very important to use good quality Acid Free and archival materials for the preservation of your treasured memories.

Carefully stored, acidic paper can have a life expectancy of 20 years or more. Exposure to light and air will quickly trigger oxidation in these lower quality papers, promoting acid migration , yellowing, off gassing, and the paper becoming brittle”. Oxidation can also happen in alkaline buffered papers that still have lignin in them, just at a slower rate. Acid free means that the paper’s pH is 7.0 (neutral) or higher (alkaline). Acid free papers can last up to 200 years under normal use and proper storage conditions.