Volume 1, Number 3
Oct 1994

Aging Behavior of Groundwood and Freesheet, Pt. 1

The graph below is based on data taken visually from two graphs on p. 199 of "The Effects of Pollution on Deacidified Paper," by Floréal Daniel, Françoise Flieder and Françoise Leclerc (Restaurator 11:179-207, 1990). The date for the two control samples is presented, to show that newsprint deteriorates more rapidly than book paper. This newsprint sample was 60% groundwood. The graph shows the increase in copper number, which is an index of oxidative degradation. A higher copper number indicates a less stable paper

The initial pH of both papers was about 5.0. Aging was done at 28°C, 90% RH, with pollution (SO₂ and NO₂ at 13 ppm and 4 ppm respectively.