Pigment Red 31

Brand	Fineland Chem
Color Index	Pigment Red 31
Color Index No	12360
CAS No	6448-96-0
EC No	229-246-9
Chemical Group	Mono Azo
Chemical Formula	C₃₁H₂₃N₅O₆

What is Pigment Red 31

Pigment Red 31 (C.I. 12100) is an organic azo pigment belonging to the β-naphthol pigment class. It produces a yellowish-red to medium red shade and has been used in traditional industrial coloration applications including coatings, printing inks, and certain plastic materials.

The pigment is synthesized through an azo coupling reaction between diazonium compounds and naphthol derivatives, forming an insoluble organic pigment with moderate tinting strength and typical characteristics of conventional azo pigments.

Pigment Red 31 is part of the broader group of classical organic red pigments used in formulations where bright coloration and relatively economical pigment chemistry are required.

Physical Properties

Test Item	Specification
Density (g/cm3 )	1.3-1.47
Specific Surface Area(m2/g)	–
Oil Absorption(g/100g)	35-52
PH Value	6-8
Bulk Density (lb/gal)	–
Total impurities(ppm)	≤600

Fastness Properties

Heat Resistance (℃)	180-200	Alkali Resistance (1-5)	5
Light Resistance (Full Shade, 1-8)	6-7	Migration Resistance(1-5)	4-5
Light (Reduced tinting, 1-8)	5-6	Ethyl Acetate (1-5)	4
Weather Resistance (1-5)	4	Ethanol (1-5)	4
Acid Resistance (1-5)	5	MEK (1-5)	3

Typical Applications

Pigment Red 31 is used in several conventional industrial coloring systems.

Typical applications include:

Industrial coatings
Used in general industrial paints and decorative coating formulations.
Printing inks
Applied in packaging inks, publication inks, and other traditional printing ink systems.
Plastic coloration
Suitable for some general-purpose plastics processed at moderate temperatures.
Rubber products
Used in rubber coloration and related industrial materials.

Key Performance Properties Related to Applications

The performance of Pigment Red 31 in various formulations is influenced by its pigment chemistry and physical characteristics.

Key properties include:

Color shade
Yellowish-red to medium red tone.
Tinting strength
Moderate tinting strength suitable for conventional coloration systems.
Dispersion properties
Can be dispersed in coating, ink, and plastic formulations using standard dispersion techniques.
Heat resistance
Moderate thermal stability typical of β-naphthol azo pigments.
Solvent resistance
Generally compatible with solvents commonly used in coatings and printing inks.

Advantages

Superior Product Performance：A synthetic monoazo pigment of the β-naphthol subclass, featuring a medium red shade (slightly yellower and less bluish than Pigment Red 22). It boasts strong color strength and high cost-effectiveness, with a light fastness rating of Grade 7, non-bleeding property, and resistance to hot water, detergents, ethanol and other media. Heat-resistant up to 280℃ for 5 minutes, it is suitable for coloring rubber, fabrics, inks, polystyrene resins and other materials.
Broad Application Prospects：Aligned with market demands in industries such as coatings, inks and plastics, it fits multiple scenarios including offset printing, packaging, and auto parts (e.g., taillights), with considerable market potential.
Reliable Supplier Strength：Decades of experience as an organic raw material supplier, continuously monitoring market demand changes to dynamically optimize product and service quality.
Comprehensive After-sales Support：Offers one-stop services including technical support, quality assurance, and product use training, with quick responses to customer inquiries and feedback.
Flexible Sample Provision：Provides product samples on demand for customer testing and evaluation, with delivery arranged according to requirements.

Typical Limitations

Pigment Red 31 may present limitations depending on the durability requirements of the final application.

Typical limitations include:

Moderate lightfastness, particularly under outdoor exposure
Limited heat resistance compared with modern high-performance pigments
Possible bleeding or migration in some plastic systems
Not generally used in applications requiring long-term weather resistance

Buyer Guidance

When evaluating Pigment Red 31 for industrial formulations, several technical considerations are commonly taken into account:

Processing temperature of plastics or coatings
Lightfastness requirements for indoor or outdoor applications
Compatibility with resin or binder systems
Dispersion behavior within the formulation

Applications requiring improved durability, higher thermal stability, or enhanced weather resistance may consider other pigment types.

Synonyms

C.I.12360	RedViolet	Pigment Red 31	Red -031-HS-1059
Red -031-PC-1048	Symular Fast Red 4085	Aquarine Red Violet 745	Duraprint Red Violet R
Suimei Fast Rnbine BB	Naphthol Red Ext Dark Shade	C.I. Pigment Red 31
3-HYDROXY-4-2-METHOXY-5-(PHENYLAMINO)CARBONYLPHENYLAZO-N-(3-NITROPHENYL)-2-NAPHTHALENECARBOXAMIDE;4-[[5-(anilino)carbonyl-2-methoxyphenyl]azo]-3-hydroxy-n-(3-nitrophenyl)naphthalene-2-carboxamide	(4Z)-4-[[2-methoxy-5-(phenylcarbamoyl)phenyl]hydrazinylidene]-N-(3-nitrophenyl)-3-oxonaphthalene-2-carboxamide;3-hydroxy-4-[[2-methoxy-5-[(phenylamino)carbonyl]phenyl]azo]-n-(3-nitrophenyl)Chemicalbook-2-naphthalenecarboxamide

Manufacturer and Supplier Information

Pigment Red 31 is manufactured by pigment producers worldwide and supplied mainly in powder form for use in coatings, inks, plastics, rubber, and related industrial applications.

Commercial grades may differ in particle size distribution, surface treatment, and dispersion characteristics depending on the intended application.

Package and Delivery

● 25KG Kraft Bag, 400kg/500kg Carton Box

● Lead Time: Normally around 15 days after signed contract.

FAQ

1.What color shade does Pigment Red 31 produce?
Pigment Red 31 typically provides a yellowish-red to medium red shade.

2.Is Pigment Red 31 an organic pigment?
Yes. It belongs to the organic azo pigment family, specifically the β-naphthol pigment group.

3.Can Pigment Red 31 be used in printing inks?
Yes. It has been used in various conventional printing ink formulations.

4.Is Pigment Red 31 suitable for high-temperature plastics?
It is generally used in plastics with moderate processing temperatures; higher-temperature polymers may require pigments with greater heat stability.