Description

2-Naphthalenesulfonic Acid, 7,7'-(Carbonyldiimino)Bis[ 4-Hydroxy-3-[(2-Methylphenyl)Azo]-, Disodium Salt is a high-purity, water-soluble azo dye intermediate and colorant. This compound is valued for its ability to impart a strong, stable color and its role in synthesizing more complex dyes and pigments. It is primarily required by manufacturers in the textile, leather, paper, and specialty ink industries for producing vibrant and durable colorations.

Application

• Primary Intermediate for Azo Dyes: Serves as a key building block in the synthesis of acid, direct, and reactive dyes for textiles and leather.
• Textile Dyeing and Printing: Used in formulations for dyeing natural and synthetic fibers, providing excellent color fastness.
• Leather Coloring Agent: Applied in the dyeing process for leather goods to achieve consistent and deep shades.
• Paper and Specialty Paper Coloring: Imparts color to paper products, including decorative and packaging papers.
• Ink Manufacturing: A component in the production of specialty inks, including inks for non-impact printing and security applications.
• Biological Staining: Potential use as a histological stain in laboratory settings due to its chromophoric properties.
• Research & Development: Utilized in chemical research for developing new chromogenic materials and studying azo chemistry.

Basic Information

Product Name	2-Naphthalenesulfonic Acid, 7,7'-(Carbonyldiimino)Bis[ 4-Hydroxy-3-[(2-Methylphenyl)Azo]-, Disodium Salt
CAS No.	72749-87-2
Molecular Formula	C40H28N6Na2O9S2
Molecular Weight	846.79 g/mol
Synonyms	Acid Red 337; C.I. 17210; 7,7'-Urylenedi(4-hydroxy-3-(o-tolylazo)-2-naphthalenesulfonic acid) disodium salt; Disodium 7,7'-(carbonyldiimino)bis(4-hydroxy-3-[(2-methylphenyl)azo]naphthalene-2-sulfonate); Azo Dye Intermediate 72749-87-2; o-Tolyl Azo Dye Salt; 2-Naphthalenesulfonic acid, 7,7'-(carbonyldiimino)bis[4-hydroxy-3-[(2-methylphenyl)azo]-, sodium salt (1:2)
EINECS	Contact for details

Quality Control

Our production of this azo dye intermediate adheres to strict quality management protocols to ensure batch-to-batch consistency and performance. Quality is verified through comprehensive analytical testing, including HPLC for purity, spectrophotometry for color strength, and elemental analysis. A detailed Certificate of Analysis (COA) documenting identity, purity, and impurity profiles 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 a controlled room temperature (15-25°C). Keep away from strong oxidizing agents and incompatible materials. The product is light-sensitive (store away from light).

Specification

Item	Specification
Appearance	Dark red to brown powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Color Strength	98 - 102% (vs. Standard)
Loss on Drying	≤ 5.0%
Sulfated Ash	≤ 20.0%
Heavy Metals (as Pb)	≤ 20 ppm
Water Solubility	Freely soluble

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