Sunset yellow is a di sodium salt of 1-(4-sulphophenylazo)-2-napthol-6-sulphonic acid. It is either available in solid or granular form. It particularly reflects orange red color.

Synonyms: C.I.Food Yellow #3
FD&C Yellow #6

No.	Molecular Description	Composition
1)	Total colour/Assay, percent by Mass, Min.	85
2)	Water-insoluble matter, percent by mass, Max.	0.2
3)	Combined ether extracts, percent by mass, Max.	0.2
4)	Subsidiary dyes, percent by mass, Max. Lower sulfonated. Higher sulfonated.	05.00
5)	Dye intermediates, percent by mass, Max. 2-Napthol-6-sulfonic acid aniline-4-sulphonic acid	00.50
6)	Unsulfonated primary aromatic amine (calculated as aniline) percent by mass, Max.	0.01
7)	Lead, mg/kg, Max. 10.00 8) Arsenic, mg/kg, Max.	3
9)	Heavy metals, (as pb) mg/kg, Max.	40
10)	Mercury, mg/kg, Max.	1
11)	Cadmium, mg/kg, Max.	1
12)	Calcium Stability	Passes The Test