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CAS 2 records

CAS 6535-42-8

CAS 6535-42-8 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 6535-42-8
CAS 6535-42-8PubChem CID 81021

1-Naphthalenol, 4-[(4-ethoxyphenyl)azo]-

IUPAC name
4-[(4-ethoxyphenyl)diazenyl]naphthalen-1-ol
Molecular formula
C18H16N2O2
Molecular weight
292.3 g/mol
Exact mass
292.121177757 Da
XLogP3
4.9
Topological polar surface area
54.2 Ų
Hydrogen-bond donors
1
Hydrogen-bond acceptors
4
Covalent units
1
Defined stereocentres
0

Also known as

Solvent red 3Fat Brown BC.I. Solvent Red 3CI 120101-Naphthalenol, 4-((4-ethoxyphenyl)azo)-4-((4-Ethoxyphenyl)diazenyl)naphthalen-1-olXNW2E182071-Naphthalenol, 4-(2-(4-ethoxyphenyl)diazenyl)-
13 more reported names
4-[(1E)-2-(4-ethoxyphenyl)diazen-1-yl]naphthalen-1-olUNII-XNW2E18207EINECS 229-439-8CERES BROWN B4-((4-Ethoxyphenyl)azo)-1-naphthalenolFat brown b, technical gradeMSK58904-((4-Ethoxyphenyl)azo)naphtholJSEYDVLGSMLKDL-UHFFFAOYSA-NBRUN FONCE AU GRAS W 82014-[(4-ethoxyphenyl)diazenyl]-alpha-naphthol4-((4-ETHOXYPHENYL)AZO)-1-NAPHTHOL(4E)-4-[(4-ethoxyphenyl)hydrazono]naphthalen-1-one
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 6535-42-8

2 total

How CAS 6535-42-8 is used on this site

CAS 6535-42-8 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 6535-42-8 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 6535-42-8 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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