Description

Dipotassium Disodium 4,4'-Bis[[4-[Bis(2-Hydroxypropyl)Amino]-6-[(4-Sulphonatophenyl)Amino]-1,3,5-Triazin-2-Yl]Amino]Stilbene-2,2'-Disulphonate is a highly specialized, water-soluble fluorescent whitening agent (FWA) belonging to the triazinylaminostilbene class. This compound is engineered to provide exceptional optical brightening effects by absorbing ultraviolet light and re-emitting it as visible blue light, thereby enhancing the perceived whiteness and brightness of treated materials. It is a critical performance additive for manufacturers in the detergent, paper, textile, and plastics industries seeking to achieve superior product aesthetics and quality.

Application

• Laundry Detergents & Fabric Softeners: Primary application as an optical brightener to impart a brilliant white appearance to cotton, polyester, and blended fabrics, counteracting yellowing.
• Paper Manufacturing: Used in coating formulations and pulp to increase the brightness and whiteness of high-quality writing, printing, and tissue papers.
• Textile Finishing: Applied in finishing baths for textiles to improve the whiteness of fibers, yarns, and finished garments, especially after bleaching.
• Synthetic Fibers & Plastics: Incorporated into polymer matrices (e.g., polyamide, polyester) during extrusion or molding to correct inherent yellowness and enhance visual appeal.
• Soaps & Personal Care Products: Utilized in certain bar soaps and cosmetic formulations where a brightening effect is desired.
• Advanced Coatings & Paints: Serves as a fluorescent additive in specialty coatings and inks to achieve optical effects and high visibility.

Basic Information

Item	Details
Product Name	Dipotassium Disodium 4,4'-Bis[[4-[Bis(2-Hydroxypropyl)Amino]-6-[(4-Sulphonatophenyl)Amino]-1,3,5-Triazin-2-Yl]Amino]Stilbene-2,2'-Disulphonate
CAS No.	49831-05-2
Molecular Formula	C52H54K2N14Na2O16S4
Molecular Weight	Approx. 1389.5 g/mol
Synonyms	Fluorescent Brightener 351; Tinopal CBS-X; 4,4'-Bis[[4-[bis(2-hydroxypropyl)amino]-6-[(4-sulfophenyl)amino]-1,3,5-triazin-2-yl]amino]stilbene-2,2'-disulfonic acid, dipotassium disodium salt; Stilbene triazine derivative; Optical Brightener OB-351; FWA 351; Disodium dipotassium 4,4'-bis(2-sulfo-4-[4,6-bis[2-hydroxypropyl)amino]-1,3,5-triazin-2-yl]aminostilbene-2,2'-disulfonate; 2,2'-(1,2-Ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl)amino]-6-[(4-sulfophenyl)amino]-1,3,5-triazin-2-yl]amino]benzenesulfonic acid] tetrasodium salt (related form)
EINECS	Contact for details

Quality Control

Our production of this fluorescent whitening agent adheres to strict quality management systems. Every batch is subjected to comprehensive analytical testing, including HPLC for purity and assay, spectrophotometry for strength and shade, and checks for solubility and ionic content. A Certificate of Analysis (COA) detailing batch-specific results is provided to ensure traceability and compliance with your technical requirements.

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 product is hygroscopic (moisture-sensitive); keep the original container tightly sealed to prevent absorption of atmospheric moisture, which can affect performance.

Specification

Item	Specification
Appearance	Yellowish to light brown powder
Identification (IR)	Conforms to standard
Assay (HPLC)	Min. 95.0%
Strength (Spectrophotometry)	100 ± 3% of standard
Moisture Content	Max. 5.0%
Water Solubility	Clear solution at 1%
pH (1% Solution)	7.0 - 9.0
Ash Content	Max. 15.0%

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