Description

Pigment Red 21 is a high-performance, synthetic organic pigment belonging to the azo chemical class, known for its vibrant and durable red hue. This pigment is valued for its excellent color strength, good dispersibility, and strong tinting properties, making it a critical component for achieving consistent and reliable coloration. It is primarily sought after by manufacturers in the coatings, plastics, printing inks, and textile industries who require stable and cost-effective red shades for their products.

Application

• Industrial and Decorative Coatings: Used in solvent-based and aqueous paint systems for automotive, architectural, and industrial finishes.
• Plastics Coloring: Imparts color to a wide range of polymers, including PVC, polyolefins, and engineering plastics for consumer goods and packaging.
• Printing Inks: A key component in formulations for offset, flexographic, and gravure inks, providing opacity and color fidelity.
• Textile Printing and Dyeing: Applied in pigment printing pastes and coatings for fabrics.
• Specialty Artists' Colors: Used in the manufacture of professional-grade oil and acrylic paints.
• Masterbatch Production: Serves as a concentrated colorant for compounding with various resin systems.

Basic Information

Product Name	Pigment Red 21
CAS No.	6410-26-0
Molecular Formula	C23H17N3O2
Molecular Weight	367.40 g/mol
Synonyms	C.I. Pigment Red 21; C.I. 12300; Brilliant Red Toner; Permanent Red Toner; Naphthol Red; 3-Hydroxy-4-[(2-methyl-5-nitrophenyl)azo]-2-naphthamide; 2-Naphthalenecarboxamide, 3-hydroxy-4-[(2-methyl-5-nitrophenyl)azo]-
EINECS	229-094-0

Quality Control

Our production of Pigment Red 21 adheres to stringent quality management protocols to ensure batch-to-batch consistency and performance reliability. Key parameters such as color strength, hue, particle size distribution, and chemical purity are rigorously tested against established internal and industry standards. A comprehensive Certificate of Analysis (COA) detailing these specifications is provided with every shipment to support your quality assurance processes.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). Keep away from incompatible materials and sources of ignition. For long-term storage, ensure containers are kept sealed to prevent moisture absorption and contamination.

Specification

Item	Specification
Appearance	Red Powder
Color Strength	100 ± 5% (vs. Standard)
Hue	Conforms to Standard
Particle Size (Residue on 45μm)	≤ 5.0%
Volatile Matter (at 105°C)	≤ 2.0%
pH Value (10% Aqueous Slurry)	6.0 - 8.0
Oil Absorption	40 - 60 g/100g
Lightfastness	≥ 5 (ISO 105-B02)
Heat Resistance	≥ 180°C

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.