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CAS 2 records

CAS 2611-82-7

CAS 2611-82-7 matches 2 EU annex records across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 2611-82-7
CAS 2611-82-7PubChem CID 17466

C.I. Acid Red 18, trisodium salt

IUPAC name
trisodium;7-hydroxy-8-[(4-sulfonatonaphthalen-1-yl)diazenyl]naphthalene-1,3-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

RefChem:1080550Ponceau 4RNew coccineAcid red 18C.I. Acid Red 18Food Red No. 102Victoria Scarlet 3RSX Purple
16 more reported names
Brilliant Scarlet 4RCoccineColacid Ponceau 4RFood Red 7Acilan Scarlet V3RAcid Brilliant Scarlet 3RCerticol Ponceau 4RSCochineal Red AAtul Acid Scarlet 3RFood Red 102Food Red Number 102C.I. Acid Red 28Edicol Supra Ponceau 4RSNeucoccinBrilliant Ponceau 3RBrilliant Scarlet 3R
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Retrieved from NIH PubChem on 2026-09-02 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Records for CAS 2611-82-7

2 total
Annex
IV
Entry
35

CI 16255

Trisodium 1-(1-naphthylazo)-2-hydroxynaphthalene-4',6,8-trisulphonate and its insoluble barium, strontium and zirconium lakes, salts and pigments

Purity criteria as set out in Commission Directive 95/45/EC (E 124)

EC
220-036-2

How CAS 2611-82-7 is used on this site

CAS 2611-82-7 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 2 EU annex records share this identifier, which helps you cross-check whether the same substance appears under one regulatory context or several.

Use this page when a supplier specification, SDS or raw-material dossier gives you CAS 2611-82-7 and you need to see every linked Annex II–VI record in one place. The entry cards above are the quickest route to concentration limits, warnings, annex placement and product-type conditions.

Frequently asked questions

A substance identified by CAS 2611-82-7 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts. For example, a substance might be restricted under Annex III with specific conditions, and the same CAS might also appear in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

Cross-reference the CAS number against your raw material specification sheets and CoA documents. When a CAS appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met in your formulation. All annex entries sharing this CAS number are listed above.

A CAS number is assigned by the Chemical Abstracts Service (USA) and is globally recognised. An EC number is a European Commission identifier from inventories such as EINECS, ELINCS or the NLP list. Both identifiers may appear in EU cosmetic annex entries. Some substances have both, some have only one, and some older entries may have neither.

The INCI Checker accepts ingredient names, CAS numbers and EC numbers. Check this CAS number directly, then verify the result against supplier specification sheets and every linked annex condition.
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