Analytical imaging of colour pigments used in Japanese woodblock prints using Raman microspectroscopy

Abstract

AbstractUkiyo‐e printing is a traditional Japanese multicolour woodblock printing style that flourished during the 18th century. Although this genre subsequently experienced a decline, interest in it has since re‐emerged. However, the materials and carving and printing technologies originally used to produce ukiyo‐e prints remain unclear due to a lack of technical information. In this study, we performed non‐invasive molecular imaging of the colour pigments in recently reproduced and original ukiyo‐e prints using Raman microspectroscopy to investigate ukiyo‐e production technologies. First, to confirm the effectiveness of this method, we obtained Raman spectral images of an ukiyo‐e print, Ohisa with a fan, that was recently reproduced using the current ukiyo‐e production protocols. The pigment species were easily identified based on their Raman spectra, and small pigment granules were observed along the paper fibres. Furthermore, we performed Raman microspectroscopy of an original ukiyo‐e print, Kabuki Actor Iwai Hanshirô VIII as Miuraya no Agemaki. Some pigment species were revealed by the Raman spectra. We also obtained high‐spatial‐resolution pigment distribution images and observed characteristic inhomogeneous colour pigment aggregations on and between the paper fibres depending on the reproduced and the original ukiyo‐e prints. Our results indicate that Raman microspectroscopy is a promising technique for determining the original ukiyo‐e print production technologies that are currently unknown.