Self-Normalized Photoacoustic Technique for the Quantitative Analysis of Paper Pigments

Abstract

A self-normalized photoacoustic technique was applied for quantitative analysis of pigments embedded in solids. Paper samples (filter paper, Whatman No. 1), attached with the pigment: Direct Fast Turquoise Blue GL, were used for this study. This pigment is a blue dye commonly used in industry to dye paper and other fabrics. The optical absorption coefficient, at a wavelength of 660 nm, was measured for this pigment at various concentrations in the paper substrate. It was shown that Beer–Lambert model for light absorption applies well for pigments in solid substrates and optical absorption coefficients as large as \(220\,\hbox {cm}^{-1}\) can be measured with this photoacoustic technique.