Why does CAS 77061-58-6 appear in more than one EU cosmetic annex?

A substance identified by CAS 77061-58-6 may appear in multiple EU cosmetic regulation annexes when it is subject to different conditions in different contexts — for example, restricted under Annex III with specific conditions, while also appearing in Annex IV as an approved colorant under separate entry conditions. Each entry must be reviewed individually.

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Use the INCI Checker on CosIng Checker with INCI names, CAS numbers or EC numbers. Paste CAS 77061-58-6 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 77061-58-6

Q: How do I use CAS 77061-58-6 for compliance screening?

Cross-reference CAS 77061-58-6 against your raw material specification sheets and CoA documents. When it appears in Annex II, verify absence. When it appears in Annex III, verify that concentration limits and product type conditions are met. All annex entries sharing this CAS number are listed on this page.

CAS 77061-58-6 matches 1 EU annex record across Annex II–VI of Regulation 1223/2009.

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Chemical identity and properties

PubChem 2D chemical structure for CAS 77061-58-6

CAS 77061-58-6PubChem CID 166491

2-(2-(4-(Dimethylamino)phenyl)diazenyl)-1,3-dimethyl-1H-imidazolium chloride (1:1)

IUPAC name: 4-[(1,3-dimethylimidazol-1-ium-2-yl)diazenyl]-N,N-dimethylaniline chloride

Molecular formula: C13H18ClN5
Molecular weight: 279.77 g/mol
Exact mass: 279.1250733 Da
Topological polar surface area: 36.8 Å²
Hydrogen-bond donors: 0
Hydrogen-bond acceptors: 4
Covalent units: 2
Defined stereocentres: 0

Also known as

Basic Red 51A7A946JJ6ICOLOREX BR51VIBRACOLOR RUBY RED2-[2-[4-(Dimethylamino)phenyl]diazenyl]-1,3-dimethyl-1H-imidazolium chloride (1:1)RefChem:561092278-601-4C.I. Basic Red 51

16 more reported names

Ruby Red2-[[4-(dimethylamino)phenyl]azo]-1,3-dimethyl-1h-imidazolium chlorideBASICRED51Basic Red 51 (Technical Grade)2-((4-(Dimethylamino)phenyl)azo)-1,3-dimethyl-1H-imidazolium chloride1H-Imidazolium, 2-[[4-(dimethylamino)phenyl]azo]-1,3-dimethyl-, chloride2-((4-(Dimethylamino)phenyl)diazenyl)-1,3-dimethyl-1H-imidazol-3-ium chloride4-[(1,3-dimethylimidazol-1-ium-2-yl)diazenyl]-N,N-dimethylaniline;chloride1H-Imidazolium, 2-((4-(dimethylamino)phenyl)azo)-1,3-dimethyl-, chloride1H-Imidazolium, 2-(2-(4-(dimethylamino)phenyl)diazenyl)-1,3-dimethyl-, chloride (1:1)1H-Imidazolium, 2-[2-[4-(dimethylamino)phenyl]diazenyl]-1,3-dimethyl-, chloride (1:1)UNII-A7A946JJ6I2-{[4-(Dimethylamino)phenyl]diazenyl}-1,3-dimethyl-1H-imidazol-3-ium chloriderojo basico 51EINECS 278-601-4rosso di base 51

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External database identifiers

EPA DTXSID:DTXSID80874049

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 77061-58-6

1 total

Annex

III

Entry

269

BASIC RED 51

2-[[4-(Dimethylamino)phenyl]azo]-1,3- dimethyl-1H-imidazolium chloride

(a) To be printed on the label: The mixing ratio. “ Hair colorants can cause severe allergic reactions. Read and follow instructions. This product is not intended for use on persons under the age of 16. Temporary ‘black…

278-601-4

Max concentration

How CAS 77061-58-6 is used on this site

CAS 77061-58-6 is the Chemical Abstracts Service identifier used to pin this page to a specific substance. In the current dataset, 1 EU annex record shares 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 77061-58-6 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 77061-58-6 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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