PONCEAU 4R |
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
b. Red solution in
water |
Maximum in water at ca 505 nm
. |
PURITY
Water Insoluble
matter |
Not more than 0.2% |
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. |