Acid-free paper
From Wikipedia, the free encyclopedia
Acid-free paper is paper that has a neutral or basic pH (7 or greater), although paper having a pH between 6 and 7 is often also considered acid-free. During production, it is treated with a mild base to neutralize the natural acids occurring in wood pulp, and it may also be buffered to prevent the formation of additional acids (as may develop from the application of sizing).
Acid-free paper is often used in books and other paper products intended to last for a long time. Paper that has not had its acidity neutralized yellows and deteriorates.
