What is Optical Brightener KSN ?

📝Product Overview

Optical Brightener KSN (Fluorescent Brightener KSN, Chemical Name: 4,4'-Bis(5-methylbenzoxazol-2-yl)diphenyl ethylene, CAS No.: 5242-49-9, Molecular Formula: C₂₈H₁₈N₂O₂) is a highly effective fluorescent brightener appearing as a pale yellow-green crystalline powder.

KSN effectively masks the yellow tint of substrates by absorbing ultraviolet light (wavelength approximately 350-360 nm) and emitting blue fluorescence (wavelength approximately 430-450 nm), imparting a bright, white visual effect to products. Key characteristics include: Excellent high-temperature resistance: Suitable for high-temperature processing (e.g., injection molding, extrusion) with a melting point of 270-280°C.

Superior light and weather resistance: Suitable for outdoor and long-term applications, maintaining lasting whitening effects.

Good compatibility: Compatible with various polymers (e.g., polyester, PC, ABS), featuring low migration and outperforming comparable products like OB-1.

Solubility: Insoluble in water, readily soluble in alkanes, mineral oils, and common organic solvents, facilitating processing.

KSN finds extensive application in synthetic polymer processing techniques including polymerization, film blowing, fiber drawing, injection molding, compression molding, and extrusion. It serves industries such as plastics, fibers, coatings, and inks.

🔬Key Specifications

Appearance ：yellow green powder

Purity,% ： 98min

Melting point,°C ：300min

Volatile conten,% ：0.3max

Ash content,% ：0.1max

Fineness.mesh ：325min

🚀Application Areas

Optical Brightener KSN is a highly effective fluorescent whitening agent widely used in various synthetic polymer materials and processing techniques, offering excellent whitening effects and processing stability. The recommended dosage is 0.01%-0.05% (depending on the substrate), and it can be formulated into whitening masterbatch (masterbatch dosage 0.5%-20%) for convenient dispersion and application. Primary applications include:

1️⃣Fiber Materials: 

Suitable for whitening synthetic fibers such as polyester (PET), polyamide (PA), polypropylene (PP) filaments, and polyacrylonitrile (PAN).

Particularly effective in high-temperature spinning and drawing processes, significantly enhancing fiber whiteness and brightness.

For natural fibers (e.g., silk and wool), suitability requires verification through specific processing protocols.

2️⃣Plastic Products: 

Used in thermoplastics and engineering plastics like polycarbonate (PC), ABS, PVC, PE, PP, EVA, and PU foam.

Suitable for processing methods including film blowing, injection molding, extrusion, and compression molding. Demonstrates outstanding whitening effects particularly in transparent films and thin-walled products.

Effectively masks yellowing in plastic items, enhancing product appearance quality.

3️⃣Other Applications: 

Widely used for whitening and brightening in coatings, inks, synthetic rubber, and artificial leather to enhance visual appeal.

Suitable for addition during polymerization of high-performance engineering plastics, excelling in applications requiring high whiteness and weather resistance.

Can be used for whitening optical transparent materials (e.g., PMMA) or high-gloss surfaces to enhance optical effects.