Fluorescence properties of naturally aged copy paper and the effect of incorporating wood extracts for their conservation

Abstract

Results from the natural aging process of copy paper using emission fluorescence spectra are presented in this article. For the study, copy paper examples subjected to aging from 0 to 25 years were selected as test samples. Copy paper shows a well-defined fluorescence spectrum due to the cellulosic compounds used in its manufacture. By analysing each sample's fluorescence bands, relative intensities and the band shifts in the paper’s fluorescence spectra, results provide information about the condition of the cellulosic compounds from which we can estimate the paper’s age. Results show that the relative intensity of fluorescence emission bands of the copy paper exponentially decay as it ages. As such, fluorescence spectroscopy stands out as a suitable technique for evaluating the deterioration suffered by, for example, art works on copy paper. The effect of incorporating wood extracts on the fluorescence properties of aged copy paper was also studied. Wood extracts soluble in ethanol and acetone appear to enhance the fluorescence emissions, raising the prospect of a novel preservation process.