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| CHOCOLATE BROWN HT |
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SYNONYMS
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CHOCOLATE BROWN * C. I. FOOD BROWN 3 * FOOD BROWN 2* BROWN HT |
| DEFINITION |
Chocolate Brown consists essentially of disodium 4,4'-(2,4-dihydroxy-5-hydroxymethyl-1,3-phenylene bisazo) di (naphthalene-l-sulfonate) and subsidiary colouring matters together with sodium chloride and/or sulfate as the principal uncoloured components.
Chocolate Brown is described as the sodium salt. The calcium and the potassium salt are also permitted. |
| CLASS |
Bisazo |
| COLOUR INDEX NO. |
20285 |
| EEC NUMBER |
E-155 |
| EINECS |
224-924-0 |
| CHEMICAL NAMES |
Disodium 4,4'-(2,4-dihydroxy-5-hydroxymethyl-1,3-phenylene bisazo) di (naphthalene-l-sulfonate) |
| CHEMICAL FORMULA |
C17H18N4Na2O9S2 |
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| MOLECULAR WEIGHT |
652.57 |
| ASSAY |
Content not less than 70% total colouring matters, calculated as the sodium salt; E 1% 1cm 403 at ca 460 nm in aqueous solution at pH7 |
| DESCRIPTION |
Reddish-brown powder |
IDENTIFICATION
a. Spectrometry
b. Brown solution in water |
Maximum in water of pH 7 at ca 460 nm |
PURITY
Water Insoluble matter |
Not more than 0.2% |
| Subsidiary colouring matters |
Not more than 10% (TLC method) |
| Organic compounds other than colouring matters |
[4-aminonaphthalene-l-sulfonic acid] - Not more than 0.7% |
| Unsulfonated primary aromatic amines |
Not more than 0.01% (Calculated as aniline) |
| Ether extractable matter |
Not more than 0.2% in a solution of pH7 |
| 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. |
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