Safranin; mono azo dyes (Ponceau RR, Fast red AV, Crocein Orange, Orange II)

Ingredients

aniline oil, tannin, antimony, iron salts, alum

Preparation Steps

Original Recipe Text

Synthetic dyes were applied to paper using various methods often adopted from textile practices. Safranine (Basic Red 2) was often applied in a two-step procedure: first, a substantive dye (like an acid dye) was applied, followed by a second dyeing with the basic dye to produce specific shades with better fastness (p. 10). For cotton and paper dyeing, various mordants such as tannin, antimony, iron salts, and alum were used to obtain specific shades (p. 9). Commercial preparations like Safranine S or Safranine MN were used for bluish or yellowish fuchsia tones respectively (p. 9).

Evidence

"the analyzed papers of the corpus, both natural and synthetic dyestuffs are encountered. The detection of synthetic dyestuff(s) is a clear evidence useable for a post quem dating of the interleaves in question."

Remarks

Safranin was invented in 1859, and mono azo dyes were developed from 1876 onwards (p. 11). These dyes arrived in big Moroccan cities like Marrakesh, Rabat, and Fes before spreading to remote areas (p. 11). They are vivid but very unstable and sensitive to water, alkali, and alcohol (p. 11).