SYNONYMS	PONCEAU 4R*C.I.FOOD RED7 * NEW COCCINE * ACID RED 18
DEFINITION	Ponceau 4R consists essentially of trisodium 2-hydroxy-1(4-sulfonato-1-naphthylazo) naphthalene-6,8-disulfonate and subsidary colouring matters together with sodium chloride and/or sodium sulfate as the principal uncoloured components.
	Ponceau 4R is described as the sodium salt. The calcium and the potassium salt are also permitted.
CLASS	Monoazo
COLOUR INDEX NO.	16255
EEC NUMBER	E-124
EINECS	220-036-2
CHEMICAL NAMES	Trisodium 2-hydroxy-1-(4-sulfonato-1-nephthylazo) naphthalene-6,8-disulfonate
CHEMICAL FORMULA	C20H11N2Na3O10S3
MOLECULAR WEIGHT	604.48
ASSAY	Content not less than 80% total colouring matters, calculated as the sodium salt.
	E 1% 1cm 430 at ca 505 nm in aqueous solution.
DESCRIPTION	Reddish powder
IDENTIFICATION
a. Spectrometry	Maximum in water at ca 505 nm .
b. Red solution in water
PURITY	Not more than 0.2%
Water Insoluble matter
Subsidiary colouring matters	Not more than 1.0%
Organic compounds other than colouring matters	[4-Aminonaphthalene-1-sulfonic acid / 7-hydroxynaphthalene-1,3-disulfonic acid / 3-hydroxynaphthalene-2,7-disulfonic acid / 6-hydroxynaphthalene-2-sulfonic acid / 7-hydroxynaphthalene-1,3-6-trisulfonic acid] - Total not more than 0.5%
Unsulfonated primary aromatic amines	Not more than 0.01% (Calculated as aniline)
Ether extractable matter	Not more than 0.2% under neutral conditions
Arsenic	Not more than 3 mg/kg.
Lead	Not more than 10 mg/kg.
Mercury	Not more than 1 mg/kg.
Cadmium	Not more than 1 mg/kg.
Heavy metals (as Pb)	Not more than 40 mg/kg.