Multi-analytic characterization of colorants in two impressions of an Utagawa Toyoharu perspective print

Two impressions of an Utagawa Toyoharu (1735–1814) perspective print were used to develop an analytical protocol for investigating traditional Edo period Japanese ink colorants. Characterization of these often sensitive colorants can help guide policies regarding the preservation of Edo period Japanese prints. As there are some visual similarities and notable differences in the colors in the two impressions, another goal of the study was to determine the correlation of the color palettes used in both impressions. This study compares the colorants in the prints to reference samples using accessible non-invasive techniques, focusing on multimodal imaging and reflectance spectroscopy. XRF and Raman spectroscopy are used to supplement analyses. Results indicate that the color palettes in the two impressions are similar and the visual differences are due to a coating on one of the prints and differing preservation histories. The study details a successful approach for the characterization of Edo period print colorants using primarily multimodal imaging and reflectance spectroscopy, while showing their limitations.