What other records share CAS 85-86-9?

CAS 85-86-9 may appear across multiple EU annex records. The CAS lookup page shows all Annex II–VI entries sharing this identifier, useful for identifying cross-annex regulatory status of the same chemical substance.

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Use the INCI Checker to screen a full ingredient list across selected markets, or use the substance market comparison to review this identity across all supported market datasets.

InventoryRef 3274414/08/2020

CI 26100

Q: What does the restriction note for CI 26100 mean?

The restriction field for CI 26100 reads: IV/51 (CI 26100) II/1353 (Solvent Red 23; CI 26100: when used as a substance in hair dye products). This is the restriction note from the CosIng inventory. For authoritative conditions and limits, always refer to the linked annex entries.

1-(4-(Phenylazo)phenylazo)-2-naphthol

CI 26100 is linked to 2 EU annex records on this page. Inventory note: IV/51 (CI 26100) II/1353 (Solvent Red 23; CI 26100: when used as a substance in hair dye products).

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Regulatory evidence by market

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Market	Evidence status	Records	Source language
European Union	Evidence linked Prohibited entry found Open this evidence	2	English and EU languages
Great Britain	Source mapped Official source mapped; ingredient rule not imported	0	English
Canada	Source mapped Official source mapped; ingredient rule not imported	0	English and French
New Zealand	Source mapped Official source mapped; ingredient rule not imported	0	English
ASEAN	Source mapped Official source mapped; ingredient rule not imported	0	English and national languages
China	Source mapped Official source mapped; ingredient rule not imported	0	Chinese with selected English material
Japan	Source mapped Official source mapped; ingredient rule not imported	0	Japanese; official English translation available
South Korea	Source mapped Official source mapped; ingredient rule not imported	0	Korean with some English names
United States	Source mapped Official source mapped; ingredient rule not imported	0	English
Australia	Source mapped Official source mapped; ingredient rule not imported	0	English
Brazil	Evidence linked Prohibited Open this evidence	1	Portuguese with INCI crosswalks
India	Source mapped Official source mapped; ingredient rule not imported	0	English and Hindi
Saudi Arabia	Source mapped Official source mapped; ingredient rule not imported	0	Arabic and English

Chemical identity and properties

PubChem 2D chemical structure for CAS 85-86-9

CAS 85-86-9PubChem CID 62331

1-(p-Phenylazophenylazo)-2-naphthol (Sudan III)

Sudan III is a bis(azo) compound that is 2-naphthol substituted at position 1 by a 4-{[(2-methylphenyl)diazenyl]phenyl}diazenyl group. A fat-soluble dye predominantly used for demonstrating triglycerides in frozen sections, but which may also stain some protein bound lipids in paraffin sections. It has a role as a carcinogenic agent, a fluorochrome and a histological dye. It is a member of azobenzenes, a member of naphthols and a bis(azo) compound. It is functionally related to a 2-naphthol. — ChEBI

IUPAC name: 1-[(4-phenyldiazenylphenyl)diazenyl]naphthalen-2-ol

Molecular formula: C22H16N4O
Molecular weight: 352.4 g/mol
Exact mass: 352.13241115 Da
XLogP3: 5.9
Topological polar surface area: 69.7 Å²
Hydrogen-bond donors: 1
Hydrogen-bond acceptors: 5
Covalent units: 1
Defined stereocentres: 0

Also known as

Sudan IIISolvent red 23C.I. Solvent Red 23Toney RedFettponceau GCerasin RedFat Scarlet LBFettscharlach

16 more reported names

CerasinrotFettrotSudan Red IIIRouge cerasineStearix ScarletPyronalrot BSudan P IIIFettscharlach LBOrganol Red BSSoudan IIICerotinscharlach RSomalia Red IIIMotirot 2RSudan Red BKFat Red RFat Red HRR

Open full PubChem record PubChem annotations 3D structure image

External database identifiers

ChEBI:CHEBI:82535
ChEMBL:CHEMBL2001927
EPA DTXSID:DTXSID3041742
PubMed:39703340
PubMed:37813177
PubMed:22287322
PubMed:20308224
PubMed:18418879
PubMed:17598027
PubMed:15822858
PubMed:15788368
PubMed:15585952
PubMed:1282215

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

Inventory details for CI 26100

INCI name

CI 26100

Description

1-(4-(Phenylazo)phenylazo)-2-naphthol

Record provenance

Inventory reference: 32744
Imported identity: CI 26100
Source update: 14/08/2020

European Commission CosIng source notes

Annex records for CI 26100

Annex II Restriction reference

Entry 1353

1-((4-Phenylazo)phenylazo)-2-naphthol (Solvent Red 23; CI 26100) when used as a substance in hair d…

CAS: 85-86-9

EC: 201-638-4

Annex IV Restriction reference

Entry 51

CI 26100 /SOLVENT RED 23

CAS: 85-86-9

EC: 201-638-4

Key data

CAS

85-86-9

201-638-4

Restriction

IV/51 (CI 26100) II/1353 (Solvent Red 23; CI 26100: when used as a substance in hair dye products)

Function

COLORANT: Exclusively or mainly intended to colour the cosmetic product, the body as a whole or certain parts thereof, by absorption or reflection of visible light. All authorised colorants are substances in the positive list of Annex IV to the Cosmetics Regulation 1223/2009.

Official EU ingredient-name evidence

The ingredient name exactly matches the official 2025 EU glossary of common ingredient names.

#6388 · CI 26100

Records sharing a CAS or EC identity

SOLVENT RED 23

Ingredients with overlapping formulation functions

CI 27290COLORANT, HAIR DYEING

CI 27755COLORANT

CI 28440COLORANT

CI 40215COLORANT

Additional official and scientific sources

11 external databases to check this identity in

Each link searches that source for this identity. What each source is, and its legal weight

ECHA CHEM / Information on chemicals PubChem PUG REST EU Safety Gate cosmetic product alerts ECHA CHEM US EPA CompTox Cosmetic Ingredient Review safety assessments FDA Global Substance Registration System ILO/WHO International Chemical Safety Cards Japan NITE-CHRIP NIOSH Pocket Guide to Chemical Hazards OECD eChemPortal

How CI 26100 appears in the CosIng inventory

The CosIng inventory lists CI 26100 as a cosmetic ingredient and this page links it to 2 annex records. The inventory entry captures names and identifiers, while the annex records show where the substance is prohibited, restricted or positively listed in EU cosmetics law.

CI 26100 is also tagged with 1 cosmetic function in the official data. Function labels describe intended use, but they do not replace regulatory review of linked annex records before formulation or labelling work.

Frequently asked questions

CI 26100 appears in the EU CosIng inventory and has linked annex records. Check the annex records above for applicable restrictions, concentration limits and conditions of use. Annex II listing means prohibited; Annex III means restricted; Annexes IV, V and VI mean permitted under specified conditions.

The restriction field for CI 26100 reads: "IV/51 (CI 26100) II/1353 (Solvent Red 23; CI 26100: when used as a substance in hair dye products)". This is the restriction note recorded in the CosIng inventory for this ingredient. For authoritative conditions and limits, always refer to the linked annex entries above.

According to the EU CosIng inventory, CI 26100 carries the following function designation(s):

COLORANT

CAS 85-86-9 may appear across multiple EU annex records. Viewing the CAS lookup page shows all Annex II–VI entries sharing this identifier, which is useful for identifying cross-annex regulatory status of the same chemical substance.

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Source note for CI 26100

This page combines the CosIng inventory entry for CI 26100 with 2 linked Annex II–VI records from the local dataset built from public European Commission cosmetic ingredient materials.

Use this inventory page to research CI 26100 and compare linked records, but verify restrictions and legal status against the current official source text and law before making regulatory decisions.

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