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Annex IV Entry 33 14/08/2020

Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate

CI 16185

Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate appears in Annex IV as a positive-list colorant entry for EU cosmetics.

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Permitted colorant— Annex IV, EU Regulation 1223/2009
Entry: 33

Chemical identity and properties

PubChem 2D chemical structure for CAS 642-59-1
CAS 642-59-1PubChem CID 13507

FD&C Red No. 2

IUPAC name
3-hydroxy-4-[(4-sulfonaphthalen-1-yl)diazenyl]naphthalene-2,7-disulfonic acid
Molecular formula
C20H14N2O10S3
Molecular weight
538.5 g/mol
Exact mass
537.98105817 Da
XLogP3
2.6
Topological polar surface area
233.0 Ų
Hydrogen-bond donors
4
Hydrogen-bond acceptors
12
Covalent units
1
Defined stereocentres
0

Also known as

EINECS 211-385-1RefChem:598827amaranth acidAmaranth (free acid)Amaranth SBordeaux SC.I. Food Red 902J7X17ZUQ
16 more reported names
FD and C Red No. 23-hydroxy-4-[(4-sulphonaphthyl)azo]naphthalene-2,7-disulphonic acidAmarantheBordeauxAizen AmaranthAmacid AmaranthAmaranth ExtraEdicol AmaranthKayaku AmaranthMaple AmaranthRakuto AmaranthAcid AmaranthAmaranth LakeJava AmaranthToyo AmaranthAmaranth A
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

PubChem 2D chemical structure for CAS 915-67-3
CAS 915-67-3PubChem CID 13506

Amaranth

Amaranth is an organic molecular entity. — ChEBI

IUPAC name
trisodium;3-hydroxy-4-[(4-sulfonatonaphthalen-1-yl)diazenyl]naphthalene-2,7-disulfonate
Molecular formula
C20H11N2Na3O10S3
Molecular weight
604.5 g/mol
Exact mass
603.92689092 Da
Topological polar surface area
242.0 Ų
Hydrogen-bond donors
1
Hydrogen-bond acceptors
12
Covalent units
4
Defined stereocentres
0

Also known as

Acid red 27Azorubin SAmaranth (dye)Food Red 9Azorubine SKayaku AmaranthJava AmaranthDolkwal Amaranth
16 more reported names
Bordeaux SDaishiki AmaranthFD & C Red No. 2Acilan Red SEC.I. Food Red 9Amaranth Dye (80%)Red No. 2Food red 2Azo Red RC.I. 16185AmarantheAmacid AmaranthEdicol AmaranthRakuto AmaranthAcid AmaranthAizen Amaranth
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Record details

Warnings

Purity criteria as set out in Commission Directive 95/45/EC (E 123)

Colour index or glossary

CI 16185

Chemical name

Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate

Chemical / IUPAC name

Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate

Color

Red

Regulatory information

Regulation

(EC) 2009/1223

See every entry this act set

Identified ingredients

Key data

CAS
642-59-1; 915-67-3
EC
211-385-1; 213-022-2
Annex
IV
Entry number
33

Inventory links for Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate

Inventory Identified ingredient
Ref 31626

ACID RED 27

CAS: 915-67-3
EC: 213-022-2
Inventory Restriction reference
Ref 32726

CI 16185

CAS: 915-67-3
EC: 213-022-2

Direct matches are limited for this record, so nearby entries from Annex IV are shown as well.

Annex IV 32
Nearby record in the same annex

CI 16035

CAS: 25956-17-6
EC: 247-368-0
Annex IV 34
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CI 16230

CAS: 1936-15-8
EC: 217-705-6
Annex IV 31
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CI 15985

CAS: 2783-94-0
EC: 220-491-7
Annex IV 35
Nearby record in the same annex

CI 16255

CAS: 2611-82-7
EC: 220-036-2
Annex IV 30
Nearby record in the same annex

CI 15980

CAS: 2347-72-0
EC: 219-073-7
Annex IV 36
Nearby record in the same annex

CI 16290

CAS: 5850-44-2
EC: 227-454-4
Annex IV 29
Nearby record in the same annex

CI 15880

CAS: 6417-83-0
EC: 229-142-3
Annex IV 37
Nearby record in the same annex

CI 17200

CAS: 3567-66-6
EC: 222-656-9
Annex IV 28
Nearby record in the same annex

CI 15865

CAS: 3564-21-4; 5280-66-0
EC: 222-642-2
Annex IV 38
Nearby record in the same annex

CI 18050

CAS: 3734-67-6
EC: 223-098-9
Annex IV 27
Nearby record in the same annex

CI 15850

EC: 226-109-5

What Annex IV means for Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate

Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate is an approved colorant listed in Annex IV of EU Cosmetics Regulation 1223/2009. Only colorants on this positive list may be used to colour cosmetic products on the EU market.

Some colorants in Annex IV are restricted by product type — for example, prohibited from use around the eyes or in products applied to mucous membranes. Check the product type and conditions fields above before use.

This record is linked to 3 CosIng inventory ingredients for name and identifier cross-reference. The page also surfaces 12 related annex records with overlapping identifiers, annex logic or naming patterns.

Compliance checklist

  • Confirm colorant is used only in permitted product types listed above.
  • Record the Colour Index number and CAS identifier in the ingredient declaration.

Frequently asked questions

Yes. Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate is included in Annex IV of EU Cosmetics Regulation 1223/2009 as a permitted colorant. Only colorants on this positive list may be used to colour cosmetic products in the EU. Check the product type conditions above for any use restrictions.

CAS 642-59-1; 915-67-3 is the unique numerical identifier assigned to Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate by the Chemical Abstracts Service. In cosmetic compliance work, the CAS number is used to cross-reference the substance across regulatory databases, raw material specifications and safety assessment reports. Multiple EU annex entries may share the same CAS number if the same substance appears under different conditions or in different annexes.

Use the INCI Checker tool on this site to paste your full ingredient list (INCI) and scan it against all Annex II–VI entries. The tool highlights any ingredients that match restricted, prohibited or allergen-flagged records. This is useful for rapid compliance screening of finished product formulas or raw material declarations.
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Source note for Annex IV record Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate

This page summarizes one Annex IV record for Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate from public European Commission cosmetic materials and adds linked inventory or identifier matches when available.

Use this record page to review Annex IV conditions for Trisodium 3-hydroxy-4-(4'-sulphonatonaphthylazo)naphthalene-2,7-disulphonate, but confirm any final regulatory decision against the current official annex wording and source files.

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