Indanthrone blue

Indanthrone blue
Names
	Other names C.I. vat blue 4, carbon paper blue, blue O, carbanthrene blue 2R, fenan blue RSN, graphtol blue RL, medium blue, monolite fast blue 3R, indanthrene, indanthrone, pigment blue 60, C.I. 69800
Identifiers
CAS Number	81-77-6 ;
3D model (JSmol)	Interactive image;
Beilstein Reference	367131
ChemSpider	6435 ;
ECHA InfoCard	100.001.251
E number	E130 (colours)
PubChem CID	6690;
CompTox Dashboard (EPA)	DTXSID2026280 ;
	InChI InChI=1S/C28H14N2O4/c31-25-13-5-1-3-7-15(13)27(33)21-17(25)9-11-19-23(21)29-20-12-10-18-22(24(20)30-19)28(34)16-8-4-2-6-14(16)26(18)32/h1-12,29-30H Key: UHOKSCJSTAHBSO-UHFFFAOYSA-N ; InChI=1/C28H14N2O4/c31-25-13-5-1-3-7-15(13)27(33)21-17(25)9-11-19-23(21)29-20-12-10-18-22(24(20)30-19)28(34)16-8-4-2-6-14(16)26(18)32/h1-12,29-30H Key: UHOKSCJSTAHBSO-UHFFFAOYAY;
	SMILES O=C6c5c4Nc3c(c2C(=O)c1ccccc1C(=O)c2cc3)Nc4ccc5C(=O)c7ccccc67;
Properties
Chemical formula	C28H14N2O4
Molar mass	442.430 g·mol−1
Appearance	dark blue solid
Density	1.6 g/ml
Solubility in water	Insoluble
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Indanthrone blue, also called indanthrene, is an organic dye made from 2-aminoanthraquinone treated with potassium hydroxide in the presence of a potassium salt. It is a pigment that can be used in the following mediums: acrylic, alkalyd, casein, encaustic, fresco, gouache, linseed oil, tempera, pastel, and watercolor painting. It is used to dye unmordanted cotton and as a pigment in quality paints and enamels. As a food dye, it has E number E130, but it is not approved for use in either the United States or the European Union.^[1] ^[2]

Properties

It has the appearance of blue needles with metallic luster and melting point of 470-500 °C. It has excellent light fastness, but may bleed in some organic solvents.

References

[1] Summary of Color Additives for Use in the United States in Foods, Drugs, Cosmetics, and Medical Devices, Food and Drug Administration

[2] Current EU approved additives and their E Numbers, Food Standards Agency

[1]

[2]