Description

7-[(2,4-Diaminophenyl)azo]-3-[[4-[[4-[[6-[(2,4-diaminophenyl)azo]-1-hydroxy-3-sodiosulfo-2-naphthalenyl]azo]phenyl]amino]-3-sodiosulfophenyl]azo]-4-hydroxynaphthalene-2-sulfonic acid sodium salt is a high-purity, complex disazo dye intermediate essential for producing deep, vibrant colors with excellent fastness properties. This compound is critical for manufacturers requiring consistent and reliable chromophores for advanced dye synthesis. It is primarily utilized by the textile, leather, and specialty ink industries for creating high-performance dyes and pigments.

Application

• Textile Dyeing: A key intermediate for synthesizing high-grade direct, acid, and reactive dyes for cotton, wool, silk, and nylon.
• Leather Coloring: Used in the production of dyes for imparting rich, durable colors to leather goods.
• Ink Manufacturing: Serves as a precursor for pigments in specialty printing inks, including inks for packaging and security applications.
• Paper Coloring: Employed in the manufacture of dyes for high-quality paper and cardboard products.
• Research & Development: Used as a standard or building block in chemical research for developing new colorants and functional materials.
• Polymer Staining: Can be utilized to create colorants for plastics and synthetic fibers.

Basic Information

Product Name	7-[(2,4-Diaminophenyl)azo]-3-[[4-[[4-[[6-[(2,4-diaminophenyl)azo]-1-hydroxy-3-sodiosulfo-2-naphthalenyl]azo]phenyl]amino]-3-sodiosulfophenyl]azo]-4-hydroxynaphthalene-2-sulfonic acid sodium salt
CAS No.	6428-37-1
Molecular Formula	C44H30N12Na2O10S2
Molecular Weight	1020.90 g/mol
Synonyms	Direct Black 38 (principal commercial name); C.I. 30235; Benzo Black; Azo Black; Direct Deep Black EW; 3,3'-[(3,3'-Dimethyl[1,1'-biphenyl]-4,4'-diyl)bis(azo)]bis[4-amino-1-naphthalenesulfonic acid] disodium salt (related isomer); Direct Black EX; Sirius Black
EINECS	229-178-9

Quality Control

Our production of this disazo dye intermediate adheres to stringent quality control protocols to ensure batch-to-batch consistency and high purity. Every lot is tested against established specifications for identity, strength, and impurity profiles. A comprehensive Certificate of Analysis (COA) detailing assay, heavy metal content, and related substance analysis is provided with each shipment to support your quality assurance processes.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, well-ventilated area at room temperature (15-25°C). This material is hygroscopic (moisture-sensitive); keep the container tightly sealed to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	Dark gray to black powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Water Content	≤ 5.0%
Sulfated Ash	≤ 20.0%
Heavy Metals (as Pb)	≤ 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.