Description

Disodium 7,7'-Iminobis[3-[(3-Aminophenyl)Azo]-4-Hydroxynaphthalene-2-Sulphonate] is a high-purity, water-soluble azo dye intermediate of significant commercial importance. Its core value lies in its ability to impart vivid, stable colors and serve as a versatile building block for synthesizing more complex dyes and pigments. This compound is essential for manufacturers in the textile, ink, and specialty chemical industries seeking reliable, high-performance colorants.

Application

• Primary intermediate for the synthesis of direct dyes and acid dyes used in textile dyeing and printing.
• Key precursor in the production of pigments for inks, coatings, and plastics.
• Used in the formulation of specialized biological stains and histochemical dyes for laboratory and diagnostic applications.
• Employed in the research and development of functional dyes for non-textile uses, such as in optical media and sensors.
• Acts as a colorant intermediate for paper and leather processing industries.

Basic Information

Product Name	Disodium 7,7'-Iminobis[3-[(3-Aminophenyl)Azo]-4-Hydroxynaphthalene-2-Sulphonate]
CAS No.	6420-39-9
Molecular Formula	C32H22N8Na2O10S2
Molecular Weight	780.68 g/mol
Synonyms	Direct Black 22 (Intermediate); C.I. 35435; 7,7'-Iminobis[4-hydroxy-3-[(3-aminophenyl)azo]-2-naphthalenesulfonic acid] disodium salt; Disodium 4,4'-[(7,7'-iminobis[4-hydroxy-3-[(3-aminophenyl)azo]-2-naphthalenesulfonate]; Azo Dye Intermediate Black 22; Aminophenyl Azo Naphthol Sulfonate Disodium Salt; Benzenesulfonic acid, 7,7'-iminobis[4-hydroxy-3-[(3-aminophenyl)azo]-2-naphthalenesulfonic acid] disodium salt
EINECS	229-185-8

Quality Control

Our production of Disodium 7,7'-Iminobis[3-[(3-Aminophenyl)Azo]-4-Hydroxynaphthalene-2-Sulphonate] adheres to stringent quality management protocols. Every batch undergoes rigorous analytical testing to ensure high purity and consistent performance. Certificates of Analysis (COA) detailing purity, identity, and impurity profiles are available upon request to support your quality assurance and regulatory needs.

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). This material is hygroscopic (moisture-sensitive); ensure the container is kept sealed to minimize exposure to atmospheric humidity.

Specification

Item	Specification
Appearance	Dark brown to black powder or crystalline solid
Identification (IR)	Conforms to structure
Assay (HPLC)	Min. 95%
Water Content (KF)	Max. 5.0%
Sulfated Ash	Max. 20.0%
Heavy Metals (as Pb)	Max. 20 ppm
Solubility (1% in Water)	Complete, clear solution

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