Skip to main content
InventoryRef 3815213/08/2020

SOLVENT ORANGE 1

4-(Phenylazo)resorcinol (CI 11920)

SOLVENT ORANGE 1 is linked to 2 EU annex records on this page. Inventory note: II/1343 (Solvent Orange 1; CI 11920: and its salts when used as a substance in hair dye products).

Regulatory evidence by market

This matrix separates verified ingredient rules from sources that are mapped but not yet imported. No imported rule does not mean the ingredient is permitted.

Compare markets

Swipe or scroll horizontally to see every column.

MarketEvidence statusRecordsSource language
European UnionEvidence linked
Prohibited entry found
Open this evidence
2English and EU languages
Great BritainSource mapped
Official source mapped; ingredient rule not imported
0English
CanadaSource mapped
Official source mapped; ingredient rule not imported
0English and French
New ZealandSource mapped
Official source mapped; ingredient rule not imported
0English
ASEANSource mapped
Official source mapped; ingredient rule not imported
0English and national languages
ChinaSource mapped
Official source mapped; ingredient rule not imported
0Chinese with selected English material
JapanSource mapped
Official source mapped; ingredient rule not imported
0Japanese; official English translation available
South KoreaSource mapped
Official source mapped; ingredient rule not imported
0Korean with some English names
United StatesSource mapped
Official source mapped; ingredient rule not imported
0English
AustraliaSource mapped
Official source mapped; ingredient rule not imported
0English
BrazilSource mapped
Official source mapped; ingredient rule not imported
0Portuguese with INCI crosswalks
IndiaSource mapped
Official source mapped; ingredient rule not imported
0English and Hindi
Saudi ArabiaSource mapped
Official source mapped; ingredient rule not imported
0Arabic and English

Chemical identity and properties

PubChem 2D chemical structure for CAS 2051-85-6
CAS 2051-85-6PubChem CID 16325

4-(Phenylazo)resorcinol

IUPAC name
4-phenyldiazenylbenzene-1,3-diol
Molecular formula
C12H10N2O2
Molecular weight
214.22 g/mol
Exact mass
214.074227566 Da
XLogP3
3.0
Topological polar surface area
65.2 Ų
Hydrogen-bond donors
2
Hydrogen-bond acceptors
4
Covalent units
1
Defined stereocentres
0

Also known as

2,4-Dihydroxyazobenzene1,3-Benzenediol, 4-(phenylazo)-1,3-Benzenediol, 4-(2-phenyldiazenyl)-RefChem:516611Sudan Orange GSolvent orange 1Ceres Orange GCeres Orange GN
16 more reported names
Sudan GFat Orange ABenzeneazoresorcinolC.I. Solvent Orange 1Sudan Yellow ARResinol Orange GFat Orange GSFat Orange RGCerisol Yellow GRGrasol Yellow RSFOrganol Orange 2JTertrogras Orange SGFat Victoria Yellow D1504 YellowC.I. Food Orange 3p-Phenylazoresorcinol
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.

Inventory details for SOLVENT ORANGE 1

INCI name

SOLVENT ORANGE 1

Description

4-(Phenylazo)resorcinol (CI 11920)

Record provenance

Inventory reference
38152
Imported identity
SOLVENT ORANGE 1
Source update
13/08/2020
European Commission CosIng source notes
Annex IV Identified ingredient
Entry 7

CI 11920

CAS: 2051-85-6
EC: 218-131-9

Key data

Restriction
II/1343 (Solvent Orange 1; CI 11920: and its salts when used as a substance in hair dye products)
Function
HAIR DYEING
Imparting color to hair. Hair dyeing preparations may be temporary, semi-permanent, or permanent, depending on the length of time the colorant remains on the hair.

Official EU ingredient-name evidence

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

Records sharing a CAS or EC identity

Ingredients with overlapping formulation functions

Additional official and scientific sources

11 external databases to check this identity in

How SOLVENT ORANGE 1 appears in the CosIng inventory

The CosIng inventory lists SOLVENT ORANGE 1 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.

SOLVENT ORANGE 1 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

SOLVENT ORANGE 1 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 SOLVENT ORANGE 1 reads: "II/1343 (Solvent Orange 1; CI 11920: and its salts 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, SOLVENT ORANGE 1 carries the following function designation(s):

CAS 2051-85-6 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.

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

Source note for SOLVENT ORANGE 1

This page combines the CosIng inventory entry for SOLVENT ORANGE 1 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 SOLVENT ORANGE 1 and compare linked records, but verify restrictions and legal status against the current official source text and law before making regulatory decisions.

Tools & next steps

Check your formula

Scan a full INCI list to detect SOLVENT ORANGE 1 and any linked EU annex restrictions or allergen flags.

INCI Checker

Search similar ingredients

Find other inventory ingredients and annex entries related to SOLVENT ORANGE 1, its identifiers or nearby name variants.

Search