A jar of Chrysophenin synthetic dye manufactured by Dahl & Co. of Barmen, Germany. Chrysophenine is an azo dye which was introduced in 1886. Dahl & Co was founded in Barmen in 1842 and started to make aniline in 1865. It amalgamated with A. Dahl, also of Barmen, in 1905 both firms merged with the aniline oil producer WUlfing to form WUlfing, Dahl & Co., which became one of the smallest firms to join I.G. Farbenindustrie AG in 1925. Part of a collection of late nineteenth and early twentieth century colorants transferred from the Colour Museum, Bradford, in 1985.
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