1.Acid-free papers are manufactured in an alkaline environment, which prevents the internal chemical deterioration of the paper over time.
The addition of calcium carbonate as a buffer also makes the paper resistant to the effects of an external acidic environment.
2.When offset papers are manufactured with a pH of 6.0 to 8.0 on a scale of 0 -14.0.
Papers are manufactured with neutral pH factors to increase the stability and improve the permanency for printing of archival records.