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Cosmetic colorants and hair dyes

Toluidine red

Also known as Hansa Red B, Helio Red Toner, Siegle Red BB

CAS 2425-85-6Formula C17H13N3O3Molar mass 307.31 g/molEC 219-372-2
GHS signal word: Danger. Pictograms: Corrosive, Hazardous to the environment 18 suppliers listed
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Toluidine red chemical structure, C17H13N3O3, CAS 2425-85-6
2D chemical structure

Key facts

What buyers check first

All properties
Appearance
Yellowish red solid
Melting point
270 to 272
Density
1.37 to 1.50 g/cm³
Solubility
Slightly soluble in water(0.8 g/L) ethanol(0.7 g/L), ethylene glycol methyl ether(0.9 g/…
HS code
292700
Category
Cosmetic colorants and hair dyes
Illustrative photo, red pigment powder in an open fibre drum in a warehouse
Typical packagingIllustrative packaging image, not the actual product

What is Toluidine red?

Plain description, key identifiers and synonyms

CI Pigment Red 3 is a member of azobenzenes.

Identifiers

Registry numbers, names and line notations, tap to copy

IUPAC name
1-[(4-methyl-2-nitrophenyl)diazenyl]naphthalen-2-ol
CAS number
2425-85-6 CAS number cross-checked
EC number
219-372-2
Molecular formula
C17H13N3O3
UNII
7K26S08256
MDL number
MFCD00003910
INCI name
CI 12120
InChIKey
ZLFVRXUOSPRRKQ-UHFFFAOYSA-N
InChI
InChI=1S/C17H13N3O3/c1-11-6-8-14(15(10-11)20(22)23)18-19-17-13-5-3-2-4-12(13)7-9-16(17)21/h2-10,21H,1H3
SMILES (canonical and isomeric)
CC1=CC(=C(C=C1)N=NC2=C(C=CC3=CC=CC=C32)O)[N+](=O)[O-]

Synonyms

  • Hansa Red B
  • Helio Red Toner
  • Siegle Red BB
  • Permanent Red 4R
  • Toluidine Red 3B
  • Fast Red R
  • Toluidine Toner
  • Independence Red
  • Helio Fast Red RN
  • Chromatex Red J
  • Toluidine Red R
  • Deep Fastona Red
  • Fastona Red B
  • Silosol Red RN
  • Hansa Scarlet RB
  • Hansa Scarlet RN
  • Siegle Red B
  • Silosol Red RBN
  • Siloton Red RLL
  • Segnale Light Red RL
  • Hansa Red G
  • Helio Red RL
  • Oralith Red P4R
  • Toluidine Red 4R
  • Carnelio Helio Red
Show all 39 synonyms
  • Eljon Fast Scarlet RN
  • Fast Red AB
  • Fast Red J
  • Fast Red JE
  • Hansa Scarlet RNC
  • Sanyo Scarlet Pure
  • Siegle Red 1
  • Silogomma Red RLL
  • Siloton Red BRLL
  • Toluidine Red BFB
  • Fastona Scarlet RL
  • Fastona Scarlet YS
  • Irgalite Red RNPX
  • Isol Fast Red HB

Physical and chemical properties

Measured values and descriptors computed from the structure

Physical and chemical properties

Measured values, check the supplier specification for your grade

Appearance
Yellowish red solidexp.
Melting point
270 to 272exp.
Density
1.37 to 1.50 g/cm³exp.
Solubility
Slightly soluble in water(0.8 g/L) ethanol(0.7 g/L), ethylene glycol methyl ether(0.9 g/L), acetone, and benzene, very soluble in mineral spirits, aromatic hydrocarbons and plasticizers.exp.

Values vary by grade. Ask suppliers for the COA or TDS of the batch you buy.

Computed descriptors

Calculated from the structure, useful for screening and formulation

Molecular weight
307.31 g/molcalc.
Exact mass
307.0957 Dacalc.
LogP (octanol/water)
5.18calc.
Topological polar surface area
88.09 Ųcalc.
Hydrogen bond donors
1calc.
Hydrogen bond acceptors
5calc.
Rotatable bonds
3calc.
Heavy atoms
23calc.
Rings
3calc.
Aromatic rings
3calc.
Fraction sp3 carbons
0.06calc.
Formal charge
0calc.
Stereocentres
0calc.
Lipinski rule of five
Passes (1 violation)calc.

Calculated for screening. Confirm critical figures with the supplier.

Murcko scaffold

The ring system that remains when every side chain is removed

Murcko scaffold of this chemical, c1ccc(N=Nc2cccc3ccccc23)cc1

c1ccc(N=Nc2cccc3ccccc23)cc1

3 rings, 18 atoms, the Diazene, naphthalenylphenyl- ring system.

1,098 other chemicals share this scaffold

Safety and hazards

GHS classification summary, not a safety data sheet

GHS signal word
Danger
GHS05: Corrosive
Corrosive
GHS09: Hazardous to the environment
Hazardous to the environment

Hazard statements

  • H318Causes serious eye damage.
  • H410Very toxic to aquatic life with long lasting effects.
  • H413May cause long lasting harmful effects to aquatic life.
Precautionary statements (7)
  • P264 + P265Wash skin thoroughly after handling. Do not touch eyes.
  • P273Avoid release to the environment.
  • P280Wear protective gloves, protective clothing, eye protection and face protection.
  • P305 + P354 + P338If in eyes: Immediately rinse with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
  • P317Get medical help.
  • P391Collect spillage.
  • P501Dispose of contents and container in accordance with local regulations.

GHS classification summary, not a safety data sheet (SDS). Classifications can differ by supplier, grade and concentration. Always check the supplier's SDS.

Full safety data and first aid

Toluidine red suppliers

Sponsored listings first, then the documented ranking: membership, verification, replies, completeness, freshness and ratings

All 18 suppliers
18 of 18 offers

Suppliers marked Unclaimed profile have not claimed their profile yet. They are not verified by CompoundList, their offers are price on request and details may have changed, so please confirm them with the supplier. Company representatives can claim a profile with a business email on the company's own website domain. Our team verifies each claim and sends the result by email.

Where suppliers are based

18 suppliers in 3 countries

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Toluidine red price

Indicative price range per kg from live supplier offers

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Uses and applications

What the substance is used for, by industry and function

Used in industrial finishes ... principal application is on air drying paints, and to a limited extent in printing inks.

Used in as a pigment in the manufacturing of paints, inks, plastics, rubber, textile printing.

One of the most widely used of all red pigments on account of the bright scarlet hue, high tinctorial strength, good fastness to acids, alkalis and to light and economy. Some limitation is improved by the relatively poor fastness to organic solvents. Widely used in paints, printing inks, emulsion paints and distempers. Other uses are in synthetic resin lacquers and leather finishes, inks for foil and tinplate printing, paper coating and dyeing, wallpaper, linoleum, carbon papers, typewriter ribbons and student-grade artist materials.

Read more

Rubber with good strength and fastness to vulcanisation but limited by solubility in rubber, celluloid, cellulose acetate, P/F, U/F, styrene and protein plastics but suffers from migration in some cases. Cement, because of fastness to lime. Textile printing for "print on" style with Aniline Black.

Industrial uses: Pigment.

Consumer uses: Pigment.

Use classes: Cosmetics.

Cosmetic ingredient, INCI name CI 12120(colorant)

Functional uses

  • Dye
  • Pigment

Cosmetic functions

  • Colorant

How it is made

Coupling diazotized 2-nitro-4-methylaniline with 2-napthol

Regulatory status

Inventories, regulations and trade controls that list this substance

Health and food

  • EU cosmetic ingredient inventory
  • EU Cosmetics Regulation Annex IV, allowed colourant
    Name: CI 12120, Ref no: 10, Annex ref: IV/10

United States

  • TSCA inventory (USA)
    Status: Active in US commerce

HS code and trade data

Customs classification and reported world trade statistics

Global trade

World import and export statistics for the HS code Toluidine red is traded under.

HS 2927.00Indicative HS code

Diazo-, azo- or azoxy compounds

World exports in 2024
$571M
+6.1% vs 2023, imports $525M
2019 to 2024
Top exporters
  1. China47.0%
  2. Indonesia13.1%
  3. Japan9.3%
Top importers
  1. United States10.2%
  2. India * partner reported9.1%
  3. South Korea9.1%

* Partner reported figures, a lower bound.

Reported customs values in USD, not prices.Full trade data

The HS code shown for Toluidine red is indicative (it was assigned by structure rules). Confirm the classification with your customs broker before shipping.

Frequently asked questions

Quick answers about Toluidine red, based on the data on this page

What is Toluidine red?

CI Pigment Red 3 is a member of azobenzenes.

What is the CAS number of Toluidine red?

The CAS registry number of Toluidine red is 2425-85-6.

What is the molecular formula and weight of Toluidine red?

The molecular formula of Toluidine red is C17H13N3O3 and its molar mass is 307.31 g/mol.

What is Toluidine red used for?

Used in industrial finishes ... principal application is on air drying paints, and to a limited extent in printing inks. Used in as a pigment in the manufacturing of paints, inks, plastics, rubber, textile printing.

Is Toluidine red hazardous?

Toluidine red carries the GHS signal word "Danger". Main hazards: causes serious eye damage, very toxic to aquatic life with long lasting effects, may cause long lasting harmful effects to aquatic life. This summary is not an SDS, always read the supplier safety data sheet.

What is the HS code of Toluidine red?

Toluidine red is usually classified under HS code 292700 (Diazo-, azo- or azoxy-compounds). This is indicative, confirm it with your customs broker before shipping.

Where can I buy Toluidine red?

CompoundList lists 18 suppliers of Toluidine red in India, China and United States. Send one free request to get and compare quotes. Your contact details stay private until you accept a quote.

Where can I buy Toluidine red in India?

13 suppliers in India list Toluidine red on CompoundList. Filter the suppliers list by country and send a request to compare prices, grades and delivery times.

What is the price of Toluidine red?

Suppliers quote Toluidine red on request because prices depend on grade, purity, quantity and destination. A free request on CompoundList gets you several quotes to compare.

Guides for buyers

Practical guides that help when you source, ship or handle Toluidine red

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Data last updated 7 Oct 2026. Details may have changed, please confirm them with the supplier. Report an error on this page
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