Pigments & Colorants
REACH
Toluidine red
CAS Number
2425-85-6
EC Number
219-372-2
Abbreviation
PR3
What is Toluidine red?
Toluidine Red (CAS 2425-85-6), also sold as C.I. Pigment Red 3, Hansa Red B, PR3 and Permanent Red 4R, is a monoazo organic pigment delivering a bright, clean red shade.
Where is Toluidine red used?
- Paints and industrial coatings: strong tinting strength and good opacity in solvent- and water-based systems
- Plastics: vivid red coloration of polyolefins and PVC in consumer goods, packaging and automotive interiors
- Printing inks: cost-effective red hues in flexographic and offset packaging and label printing
- Leather finishes and paper colorants rely on this pigment for surface dyeing.
Good to know: Consistent shade and batch-to-batch reproducibility are critical procurement criteria.
Commercial specifications
- Standard commercial grades at varying pigment concentrations
Other Names (Synonyms)
C.I. Pigment Red 3|Hansa Red B|Permanent Red 4R|Fast Red R|Toluidine Toner|Independence Red|Helio Fast Red RN|Chromatex Red J|PR3
What are the physical properties of Toluidine red?
Melting Point 270-272 °C(lit.)
Boiling Point 447.81°C (rough estimate)
Density 1.1873 (rough estimate)
Appearance red to orange powder
Form neat
Water Solubility 211μg/L at 20℃
Refractive Index 1.6500 (estimate)
Log P 5.4 at 25℃
How is Toluidine red classified and handled safely? Learn More
Danger
GHS05· Corrosive GHS09· Environmental Hazard
Hazard Statements
H318 Causes serious eye damage
H410 Very toxic to aquatic life with long lasting effects
H413 May cause long lasting harmful effects to aquatic life
Precautionary Statements
P273 Avoid release to the environment.
P280 Wear protective gloves/protective clothing/eye protection/face protection.
P317 Get emergency medical help.
P391 Collect spillage.
Which trade and regulatory codes apply to Toluidine red?
UN Number 3077
ADR Class 9
Packing Group III
WGK (Germany) 3