Black 7984

Black 7984, Food Black 2, or C.I. 27755, is a brown-to-black synthetic diazo dye. It is often used as the tetrasodium salt.

Black 7984

Names
IUPAC name Tetrasodium 6-amino-4-hydroxy-3-[[7-sulfonato-4-[(4-sulfonatophenyl)azo]-1-naphthyl]azo]naphthalene-2,7-disulfonate
Other names Food Black 2 C.I. 27755
Identifiers
CAS Number	2118-39-0 Y acid: 25738-38-9
3D model (JSmol)	Interactive image acid: Interactive image
ChemSpider	acid: 14306907
ECHA InfoCard	100.016.661
EC Number	218-326-9
PubChem CID	14047491
CompTox Dashboard (EPA)	DTXSID40879792
InChI InChI=1S/C26H19N5O13S4.4Na/c27-20-12-18-13(9-23(20)47(39,40)41)10-24(48(42,43)44)25(26(18)32)31-30-22-8-7-21(17-6-5-16(11-19(17)22)46(36,37)38)29-28-14-1-3-15(4-2-14)45(33,34)35;;;;/h1-12,30H,27H2,(H,33,34,35)(H,36,37,38)(H,39,40,41)(H,42,43,44);;;;/q;4*+1/p-4/b29-28?,31-25-;;;; Key: XAOPCPOUYMCJFA-PEEPPZCGSA-J acid: InChI=1S/C26H19N5O13S4/c27-20-12-18-13(9-23(20)47(39,40)41)10-24(48(42,43)44)25(26(18)32)31-30-22-8-7-21(17-6-5-16(11-19(17)22)46(36,37)38)29-28-14-1-3-15(4-2-14)45(33,34)35/h1-12,32H,27H2,(H,33,34,35)(H,36,37,38)(H,39,40,41)(H,42,43,44)/b29-28+,31-30+ Key: DUUHLAZWLLCPSP-DUJDKOHPSA-N
SMILES [O-]S(C(C=C4)=CC=C4/N=N/C(C=C2)=C3C(C=C(S([O-])(=O)=O)C=C3)=C2/N=N/C1=C(S([O-])(=O)=O)C=C(C=C(S([O-])(=O)=O)C(N)=C5)C5=C1O)(=O)=O.[Na+].[Na+].[Na+].[Na+] acid: Nc1cc2c(O)c(/N=N/c3ccc(/N=N/c4ccc(S(=O)(=O)O)cc4)c4ccc(S(=O)(=O)O)cc34)c(S(=O)(=O)O)cc2cc1S(=O)(=O)O
Properties
Chemical formula	C26H15N5Na4O13S4
Molar mass	825.63 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

When used as a food dye, it has E number E152. Its use in food has not been permitted in the United States and in the European Union since 1984. It is also not permitted in Australia and Japan.

Black 7984 is also used in cosmetics.

See also

• Carbon black