from PhysicsWeb
Water pores reveal age of paper
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Yet another scientific analytical tool in estimating the age of paper-based materials (also see earlier post on the "print-clock"). This new technique looks at the molecular structure of cellulose fibres present in paper and measuring the size of pores which holds water in the cellulose molecule, which increases over time. In the abstract, there is a mention of the protective effect of gelatine sizing on paper.