Toluidine Red

Description

Toluidine Red · CAS 2425-85-6 · C17H13N3O3. UNII 7K26S08256. Melting Point: 518 to 522 °F (NTP, 1992); Melting Point: 270 to 272 °C; Color Additive Status: 81.30.

Identification

CAS Registry Number	2425-85-6
PubChem CID	17047
Molecular formula	C17H13N3O3
IUPAC name	1-[(4-methyl-2-nitrophenyl)diazenyl]naphthalen-2-ol
UNII (FDA)	7K26S08256

Computed Descriptors

Molecular Weight	307.30
XLogP3	4.8
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	5
Rotatable Bond Count	2
Exact Mass	307.09569129
Monoisotopic Mass	307.09569129
Topological Polar Surface Area	90.8
Heavy Atom Count	23
Formal Charge	0

Physical & Chemical Properties

Melting Point	518 to 522 °F (NTP, 1992)
Melting Point	270 to 272 °C
Color Additive Status	81.30

Physical description & handling notes

• Yellowish-red to red powder or solid. (NTP, 1992)
• CBI; Dry Powder
• Yellowish-red to red solid; [CAMEO]
• Yellowish red solid
• Hue varies considerably with particle size and therefore several shades are commercially available.
• less than 1 mg/mL at 72 °F (NTP, 1992)

Regulatory Status

Regulatory & Food Contact	CIR / INCI: Cosmetic colorant
GHS notification summary	56.9% (246 / 432)

GHS Hazard Classification

GHS notification summary	56.9% (246 / 432)
Reported hazard statements	H318 (18.8%), H410 (18.8%), H413 (24.1%)

Documented Uses

• Used in paints, inks, plastics, rubber, cement, textile printing, and munitions; [HSDB]
• Painting (Pigments, Binders, and Biocides) [Category: Paint]
• Textiles (Printing, Dyeing, or Finishing) [Category: Industry]
• 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
• Information on 4 consumer products that contain CI Red Pigment 3 in the following categories is provided:

Synonyms

2425-85-6; Toluidine red; 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

Frequently Asked Questions

What are the CAS number and molecular formula of Toluidine Red?

CAS 2425-85-6; molecular formula C17H13N3O3; molecular weight — g/mol.

What other names is Toluidine Red known by?

2425-85-6, Toluidine red, Hansa Red B, Helio Red Toner, Siegle Red BB, Permanent Red 4R.

What is the regulatory status of Toluidine Red?

Documented regulatory listings: CIR / INCI: Cosmetic colorant.

Is Toluidine Red classified as hazardous?

56.9% of GHS notifications report no hazard classification (246 of 432).

What are the key physical properties of Toluidine Red?

Melting Point: 518 to 522 °F (NTP, 1992); Melting Point: 270 to 272 °C; Color Additive Status: 81.30.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.