Solvent Red 26

Solvent Red 26, also known as Oil Red EGN or C.I. 26120, is a purplish red synthetic azo dye. It is soluble in oils and insoluble in water.

Solvent Red 26

Names
Other names Oil Red EGN, Benzidine Yellow 10G, Sanyo Pigment Yellow 8105
Identifiers
CAS Number	4477-79-6
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL1966947
ChemSpider	16097342
ECHA InfoCard	100.022.508
EC Number	224-757-3
PubChem CID	62541
UNII	KR6F64FLX3 Y
CompTox Dashboard (EPA)	DTXSID5050395
InChI InChI=1S/C25H22N4O/c1-16-8-4-7-11-21(16)26-27-22-14-18(3)23(15-17(22)2)28-29-25-20-10-6-5-9-19(20)12-13-24(25)30/h4-15,30H,1-3H3 Key: NRBKWAQSLYBVSG-UHFFFAOYSA-N
SMILES Oc2ccc1ccccc1c2N=Nc3cc(C)c(N=Nc4ccccc4C)cc3C
Properties
Chemical formula	C25H22N4O
Molar mass	394.478 g·mol−1
Appearance	Red solid
Solubility in water	Low
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H317, H319, H335, H341, H351
Precautionary statements	P201, P202, P261, P264, P271, P272, P280, P281, P302+P352, P304+P340, P305+P351+P338, P308+P313, P312, P321, P332+P313, P333+P313, P337+P313, P362, P363, P403+P233, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Its main use is as a standard fuel dye in the US mandated by the US IRS to distinguish low-taxed or tax exempt heating oil from automotive diesel fuel, and by the EPA to mark fuels with higher sulfur content; it is however increasingly replaced with Solvent Red 164, a similar dye with longer alkyl chains, which is better soluble in hydrocarbons.^[1] The concentration required by IRS is a spectral equivalent of 3.9 pounds per 1000 barrels, or 11.13 mg/L, of Solvent Red 26 in solid form; the concentrations required by EPA are roughly 5 times lower.

See also

• Solvent Red 27
• Solvent Red 164