Why does CAS 2390-59-2 appear in more than one EU cosmetic annex?

A substance identified by CAS 2390-59-2 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 2390-59-2 to screen it directly, then review every linked annex record and supplier document.

CAS 1 record

CAS 2390-59-2

Q: How do I use CAS 2390-59-2 for compliance screening?

Cross-reference CAS 2390-59-2 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 2390-59-2 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 2390-59-2

CAS 2390-59-2PubChem CID 16955

Basic Violet 4

Ethyl violet is an organic chloride salt that is the monochloride salt of ethyl violet cation. Used for inclusion in mixed dye solutions of the iron resorcin fuchsin type for demonstrating elastic fibres. It has a role as a fluorochrome and a histological dye. It contains an ethyl violet cation. — ChEBI

IUPAC name: [4-[bis[4-(diethylamino)phenyl]methylidene]cyclohexa-2,5-dien-1-ylidene]-diethylazanium chloride

Molecular formula: C31H42ClN3
Molecular weight: 492.1 g/mol
Exact mass: 491.3067260 Da
Topological polar surface area: 9.5 Å²
Hydrogen-bond donors: 0
Hydrogen-bond acceptors: 3
Covalent units: 2
Defined stereocentres: 0

Also known as

Ethyl violetC.I. Basic Violet 4Ethyl Violet AXEthyl Violet GGALowacryl Violet 4Ethyl crystal violetC.I. 42600Shikiso Acid Brilliant Blue 6B

16 more reported names

Ethyl Violet (Biological Stain)94UZ9RD7TJNSC-8675Ethanaminium, N-(4-(bis(4-(diethylamino)phenyl)methylene)-2,5-cyclohexadien-1-ylidene)-N-ethyl-, chlorideCHEBI:88010CI 42600Ethanaminium, N-(4-(bis(4-(diethylamino)phenyl)methylene)-2,5-cyclohexadien-1-ylidene)-N-ethyl-, chloride (1:1)Ethanaminium, N-[4-[bis[4-(diethylamino)phenyl]methylene]-2,5-cyclohexadien-1-ylidene]-N-ethyl-, chlorideRefChem:596440(4-(bis(4-(diethylamino)phenyl)methylene)-2,5-cyclohexadien-1-ylidene)diethylammonium219-231-5246-781-3Ethanaminium,N-[4-[bis[4-(diethylamino)phenyl]methylene]-2,5-cyclohexadien-1-ylidene]-N-ethyl-, chloride[4-[bis[4-(diethylamino)phenyl]methylidene]cyclohexa-2,5-dien-1-ylidene]-diethylazanium;chlorideN-(4-(Bis(4-(diethylamino)phenyl)methylene)cyclohexa-2,5-dien-1-ylidene)-N-ethylethanaminium chloride(4-(Bis(4-(diethylamino)phenyl)methylene)-2,5-cyclohexadien-1-ylidene)diethylammonium chloride

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:88010
ChEMBL:CHEMBL1698845
EPA DTXSID:DTXSID5038913

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 2390-59-2

1 total

Annex

Entry

1271

Ethanaminium, N-(4-[bis[4-(diethylamino)phenyl]methylene]-2,5-cyclohexadien-1-ylidine)-N-ethyl- and its salts, when used as a substance in hair dye products

219-231-5

How CAS 2390-59-2 is used on this site

CAS 2390-59-2 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 2390-59-2 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 2390-59-2 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.

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