WSD CHEMICAL’s full series of plastic-specific fluorescent brighteners are high-efficiency optical brightening additives designed to eliminate the inherent faint yellow tint of plastic substrates through a non-bleaching optical compensation mechanism. These compounds contain a conjugated π-electron system with rigid planar molecular structures, which can absorb invisible ultraviolet light in the 340-400nm wavelength range and re-emit it as visible blue-violet fluorescence. This emitted light perfectly complements the residual yellow light on the plastic surface, significantly lifting visual whiteness, brightness and vividness without altering the material’s original chemical composition.

Our core product portfolio covers multiple mainstream technical grades tailored for different plastic systems: OB series (FBA 184), a benzoxazole-type grade with excellent heat resistance up to 220°C, widely compatible with PVC, PE, PP, PS and ABS; OB-1, a high-temperature resistant grade stable above 280°C, perfectly suited for polyester fiber, engineering plastics and high-speed thin film processing; and other specialized grades optimized for low migration, high weather resistance or specific resin compatibility. Each product is strictly controlled for purity and impurity content to avoid fluorescence quenching, yellowing or negative impact on plastic mechanical properties. The recommended total dosage usually ranges from 0.0005% to 0.05% by weight, with excessive addition strictly avoided to prevent bluish discoloration on the finished surface.

These fluorescent brighteners are widely applied in PVC profiles, sheets, plastic films, injection-molded household products, synthetic fibers, foamed materials and plastic packaging. They can raise the D65 light source whiteness index by more than 15 units, delivering a clean, bright and premium visual appearance. All products are free-flowing fine powders, packed in 25kg light-proof sealed drums, stored in cool, dry and shaded warehouses with a 24-month shelf life.