Why Does Paper Deteriorate?
Until the mid 19th century, most papers were made of cotton rags or cloth stock. Around 1860 the paper mills started using ground wood with acids, bleach, and alum-rosin sizing resulting in papers with a high acid content (low pH). These papers react with water and the atmosphere to produce self-destructive acidic compounds. These acids act on the paper and shorten the fibres, causing them to become brittle, dis-coloured and eventually crumble into dust. (S.
