Description

4,4'-Bis[[6-Anilino-4-(Methylamino)-1,3,5-Triazin-2-Yl]Amino]Stilbene-2,2'-Disulphonic Acid is a high-performance fluorescent whitening agent (FWA) belonging to the triazinylaminostilbene class, valued for its exceptional optical brightening properties. This compound is engineered to absorb ultraviolet light and re-emit it as visible blue light, effectively counteracting yellowing and enhancing the perceived whiteness and brightness of materials. It is a critical component for manufacturers in the detergent, paper, textile, and plastics industries seeking to achieve superior product aesthetics and market competitiveness.

Application

• Detergent & Laundry Care: Primary application as an optical brightener in laundry detergents, powders, and liquids to make white fabrics appear brighter and colored fabrics more vivid.
• Paper Manufacturing: Used in the production of high-quality writing, printing, and tissue papers to achieve a high degree of whiteness and opacity.
• Textile & Fiber Treatment: Applied in the finishing of cotton, nylon, and other synthetic fibers to improve whiteness, especially for materials that yellow with age or exposure.
• Plastics & Polymers: Incorporated into polymers like PVC, polyolefins, and styrenics to mask inherent yellowness and produce bright, white finished plastic products.
• Cosmetics & Personal Care: Utilized in certain formulations, such as soaps and shampoos, to enhance visual appeal through brightening effects.
• Coatings & Paints: Serves as an additive in coatings and white paints to improve brightness and achieve a cleaner visual tone.

Basic Information

Product Name	4,4'-Bis[[6-Anilino-4-(Methylamino)-1,3,5-Triazin-2-Yl]Amino]Stilbene-2,2'-Disulphonic Acid
CAS No.	35632-99-6
Molecular Formula	C34H32N12O6S2
Molecular Weight	784.83 g/mol
Synonyms	Fluorescent Brightener 351; Tinopal UNPA-GX; Stilbene triazine fluorescent whitening agent; 4,4'-Bis[(4-anilino-6-methylamino-1,3,5-triazin-2-yl)amino]stilbene-2,2'-disulfonic acid; UNPA-GX; FWA 351; CBS 351; Optical Brightener 351
EINECS	Contact for details

Quality Control

Our production of 4,4'-Bis[[6-Anilino-4-(Methylamino)-1,3,5-Triazin-2-Yl]Amino]Stilbene-2,2'-Disulphonic Acid adheres to stringent quality management protocols to ensure batch-to-batch consistency and performance reliability. Each lot undergoes comprehensive analysis, including HPLC assay for purity, spectrophotometric analysis for strength and hue, and tests for solubility and residual solvents. Certificates of Analysis (COA) documenting all critical parameters are provided with every shipment to support your quality assurance and regulatory compliance 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). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed after opening to prevent moisture absorption, which can affect performance. Keep away from incompatible materials.

Specification

Item	Specification
Appearance	Light yellow to yellow powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 95.0%
Moisture (KF)	≤ 5.0%
Ash Content	≤ 0.5%
Fluorescent Strength	100 ± 5% (vs. Standard)
Shade	Standard Blue-Violet
Solubility (in Water)	Partially soluble, forms colloidal dispersion

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