Description

Disodium 4,4'-Bis[(4-Hydroxy-3-Methylphenyl)Azo]Stilbene-2,2'-Disulphonate is a high-purity, synthetic organic dye belonging to the class of disulfonated azo-stilbene derivatives. This compound is valued for its strong and stable color properties, making it a critical component in industrial applications requiring precise and durable coloration. It is primarily utilized by manufacturers in the paper, textile, and specialty chemical industries where consistent quality and performance are paramount.

Application

• Paper Dyeing: Used as a direct dye for coloring various grades of paper, providing bright and uniform shades with good fastness properties.
• Textile Auxiliary: Functions as a dye intermediate or finishing agent for synthetic and natural fibers to achieve specific color effects.
• Specialty Inks: Employed in the formulation of inks for security printing, packaging, and other applications requiring high color strength.
• Leather Coloring: Used in the dyeing process for leather goods to impart vibrant and lasting color.
• Laboratory Reagent: Serves as a chemical standard or reagent in analytical and research laboratories for colorimetric analysis.
• Optical Brightener Intermediate: Acts as a key precursor in the synthesis of certain optical brightening agents (fluorescent whitening agents).

Basic Information

Product Name	Disodium 4,4'-Bis[(4-Hydroxy-3-Methylphenyl)Azo]Stilbene-2,2'-Disulphonate
CAS No.	62037-55-2
Molecular Formula	C34H26N4Na2O8S2
Molecular Weight	728.68 g/mol
Synonyms	Direct Yellow 11; C.I. 40000; Stilbene Yellow; 4,4'-Bis[(4-hydroxy-3-methylphenyl)azo]-2,2'-stilbenedisulfonic acid disodium salt; Disodium 4,4'-[1,2-ethenediylbis[(2-sulfo-4,1-phenylene)azo]]bis[2-methylphenol]; Paper Yellow R; Amanil Yellow G; Azo Stilbene Dye
EINECS	263-357-5

Quality Control

Our production of Disodium 4,4'-Bis[(4-Hydroxy-3-Methylphenyl)Azo]Stilbene-2,2'-Disulphonate adheres to stringent quality management protocols to ensure batch-to-batch consistency and purity. All material is subjected to comprehensive analytical testing, including chromatographic and spectroscopic methods. A Certificate of Analysis (COA) detailing purity, identity, and key physical parameters is provided with every shipment to guarantee compliance with your specifications.

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). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed to prevent absorption of atmospheric moisture, which may affect product performance.

Specification

Item	Specification
Appearance	Orange to reddish-brown powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
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.