Erythrosine
iodo-derivative of fluorone used as a pink dye
Erythrosine, also known as E127 and Red No. 3, is an organoiodine compound, specifically a derivative of fluorone. It is a red-pink dye used for food coloring, cosmetics, hair coloring, pet products, and diverse industrial colorings. It is the disodium salt of 2,4,5,7-tetraiodofluorescein.
History
The colorant was discovered by the Swiss chemist Karl Kussmaul at the University of Basel in 1876 and soon commercialized by the local Bindschedler & Busch company for dyeing wool and silk. Its use as a textile dye was soon superseded due to its propensity to fade in sunlight.
Its use as a food dye was legalized in the US by the Pure Food and Drug Act of 1906. By early 1920s, it was produced mainly for the food industry, with 2,170 pounds (0.98 t) made in America in 1924, rising to 9,468 pounds (4.29 t) in 1938 and approximately 50 tons in 1967.
Production
Erythrosine is synthesized from resorcinol and phthalic anhydride, which are processed into fluorescein. Fluorescein then undergoes iodination, producing the bright red dye.
“Erythrosine” enters the record as iodo-derivative of fluorone used as a pink dye. Crown Archives preserves that source wording while asking what Erythrosine, iodo-derivative and fluorone can confirm, complicate or overturn.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Sep 5, 2026. The linked authority identifier is Q420101. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1876, 1906, 1924 and 1938.
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