Sappanwood: Ukiyo-e colorant

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Stone by Katsushika Hokusai

Sappanwood 蘇芳 (suō): A red dye extracted from any of several tropical trees of the senna genus, Caesalpinia, such as C. brasiliensis (from Brazil), C. crista (from Pernambuco), C. echinata (peachwood from Nicaraugua), or C. sappan (sappanwood from East Indies and Asia). Its principal colorant is Brasilin, a hydroxyanthraquinone, that gives a deep red to brownish color when it is oxidized to form brasilein.

Sappanwood has been detected but the use of it appears to have been infrequent. It also appears to have been used as a mixture with safflower or madder. Due to its sensitivity to pH, sappanwood can be manipulated to produce a range of colors as pink, red, or oranges. It is unknown if printers adjusted the pH to create a range of colors. Evidence of pH manipulation is difficult to extrapolate from the prints themselves since many of the examples have discolored to a dull pinkish brown due to fading and/or ageing.

For more information see: Sappanwood, Uemura Dye Archive: Sappanwood 287, 288, 289, 290, 291, 292, 294, 295

Examples of Sappanwood in Ukiyo-e Prints

11.13225-pt8-detail.png

11.13225 Pt 8 EEM.jpg
Pt 8: hand applied
Okumura Toshinobu, 11.13225

11.30137-pt1-detail.png

11.30137 EEM Jul 19 2016.jpg
Pt 1: printed
Komatsuken, 11.30137

11.20413-pt5-detail.png

11.20413 EEM Feb 6 2019.jpg
Pt 5: printed
Katsushika Hokusai, 11.20413

21.9257-pt4-detail.png

21.9257 EEM Pt 4 Jan 8 2020.jpg
Pt 4: printed
Yanagawa Shigenobu I, 21.9257

11.25669-pt2-detail.png

Indigo FORS.JPG
Pt 2: printed
Keisai Eisen, 11.25669

Analysis

Excitation Emission Matrix (EEM) spectroscopy can easily identify the organic reds: safflower, madder, and sappanwood. Sappanwood does not fluoresce which produces an EEM pattern different from safflower and madder. Sappanwood has an Excitation maximum at 570 +/− 10nm and an Emission maximum about 600 +/− 10nm.


Images of Sappanwood

List of Prints

Below is a list of prints where sappanwood was detected.

Pages in category "Sappanwood: Ukiyo-e colorant"

The following 33 pages are in this category, out of 33 total.