Description

Disodium 2,2'-(Azoxydi-p-Phenylene)Bis[6-Methylbenzothiazole-7-Sulphonate] is a high-purity, water-soluble fluorescent whitening agent (FWA) belonging to the stilbene-benzothiazole chemical class. This compound is valued for its exceptional ability to absorb ultraviolet light and re-emit it as a bright blue fluorescence, effectively compensating for yellowish tints and enhancing the perceived whiteness and brightness of materials. It is primarily utilized by manufacturers in the paper, textile, detergent, and plastics industries seeking to achieve superior optical brightening effects in their final products.

Application

• Paper Manufacturing: As a key optical brightening agent (OBA) in high-quality printing, writing, and specialty papers to achieve brilliant whiteness.
• Textile & Fiber Processing: For whitening and brightening natural and synthetic fibers, including cotton, polyester, and polyamide blends during finishing stages.
• Detergent & Laundry Care Formulations: Incorporated into premium laundry detergents and fabric conditioners to impart a "whiter-than-white" appearance to laundered fabrics.
• Plastics & Polymer Industry: Used as a fluorescent whitener in polymers, synthetic fibers (like polyamide), and masterbatches to correct yellowness and enhance visual appeal.
• Advanced Coating Systems: Applied in coatings, varnishes, and inks where optical brightness is a critical performance parameter.
• Soap & Personal Care Products: For whitening applications in certain soap bars and cosmetic formulations where a brightening effect is desired.

Basic Information

Product Name	Disodium 2,2'-(Azoxydi-p-Phenylene)Bis[6-Methylbenzothiazole-7-Sulphonate]
CAS No.	83006-45-5
Molecular Formula	C30H20N4Na2O8S4
Molecular Weight	738.73 g/mol
Synonyms	Disodium 4,4'-bis(6-methyl-7-sulfonato-2-benzothiazolyl)azobenzene; Disodium 4,4'-bis(6-methyl-7-sulfonato-2-benzothiazolyl)diphenyldiazene; Fluorescent Brightener 351; FWA 351; Optical Brightener 351; OB-1 (industry-specific); 2,2'-(1,2-Diphenyldiazene-1,2-diyl)bis[6-methyl-1,3-benzothiazole-7-sulfonic acid] disodium salt
EINECS	Contact for details

Quality Control

Our production of Disodium 2,2'-(Azoxydi-p-Phenylene)Bis[6-Methylbenzothiazole-7-Sulphonate] adheres to stringent quality management protocols. Each batch undergoes rigorous analytical testing to ensure consistent purity, performance, and compliance with industry specifications. Certificates of Analysis (COA) detailing key parameters such as assay, hue, and solubility are provided to guarantee product integrity and traceability for our global B2B clients.

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 after each use to prevent moisture absorption and degradation of the product.

Specification

Item	Specification
Appearance	Yellowish to light brown powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Moisture Content	≤ 5.0%
pH (1% Solution)	7.0 - 9.0
Water Solubility	Freely soluble
Fluorescence Intensity	Meets standard reference
Ash Content	≤ 0.5%

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