Naphthol green B is an organic sodium salt composed of iron(3+), sodium and 5-(oxidoimino)-6-oxo-5,6-dihydronaphthalene-2-sulfonate ions in a 1:1:3 ratio.Its absorption maximum is 714 nm in water. It is water-soluble.
Naphthol Green B is a coordination complex of iron that is used as a dye.Naphthol Green B is the sodium salt of Naphthol Green Y (C.I. 10005). The organic ligands each bind to iron as bidentate ligands through the nitrogen and the anionic phenoxide groups. It contains a 5-(oxidoimino)-6-oxo-5,6-dihydronaphthalene-2-sulfonate.