Optical brightener OB-1 is one of the most widely used and highly effective fluorescent whitening agents in the plastics and synthetic fiber industries. Known for its strong fluorescence, excellent thermal stability, and high whitening efficiency, OB-1 is the preferred choice for engineering plastics and fiber-grade polymers processed under high temperatures.
This article provides a detailed technical profile of optical brightener OB-1, including specifications, performance characteristics, and application fields.
1. Chemical Identity and Molecular Properties
- Product Name: Optical Brightener OB-1
- Chemical Name: 2,2’-(4,4’-distyryl)bisbenzoxazole
- C.I. Number: 393
- CAS Number: 1533-45-5
- Molecular Formula: C₂₈H₁₈N₂O₂
- Molecular Weight: 414.45
Optical brightener OB-1 belongs to the benzoxazole class of fluorescent whitening agents. Its rigid, conjugated molecular structure provides high photostability, strong fluorescence, and exceptional heat resistance—properties that make OB-1 ideal for polymers requiring high-temperature processing.
2. Technical Specifications
| Parameter | Value |
|---|---|
| Appearance | Yellowish-green crystal powder |
| Assay (Content) | ≥ 98.5% |
| Melting Point | 355–360°C |
| Volatile Matter | ≤ 0.5% |
| Ash Content | ≤ 0.5% |
| Max Absorption Wavelength | 374 nm (ethanol) |
| Max Emission Wavelength | 434 nm (ethanol) |
Solubility Profile
- Poorly soluble in water
- Soluble in alkane, mineral oil, and most common organic solvents
This solubility pattern supports excellent dispersion in hydrophobic polymer systems.
3. Performance and Application Fields
Optical brightener OB-1 is widely used in industry due to its:
- High whitening intensity
- Strong blue-violet fluorescence
- Excellent heat resistance (stable up to 360°C)
- Good photostability in polymer matrices
Primary Applications
✓ Polyester (PET)
OB-1 provides bright, clean whiteness for PET fibers, films, and injection-molded products. Its high thermal stability makes it suitable for polyester melt spinning and molding.
✓ Polyamide (Nylon)
OB-1 is one of the few whitening agents capable of withstanding nylon’s high processing temperature (≥280°C). It enhances brightness without degrading or forming residues.
✓ Various Plastics
OB-1 is widely used in:
- PP, PE
- PS, ABS
- Engineering plastics
- Recycled plastics requiring optical enhancement
Its strong fluorescence and wide compatibility allow it to improve the appearance of both virgin and recycled materials.
4. Packaging
- Standard Packaging: 25 kg fiber drum
- Inner Lining: Double-layer plastic bag for moisture and contamination protection
5. Handling & Transportation
To maintain quality and performance, optical brightener OB-1 should be protected from:
- Sunlight
- Moisture
- Physical impact
- Package damage
Inversion or heavy compression should be avoided during transport.
6. Storage Guidelines
- Store in a cool, dry, and well-ventilated area
- Keep the container tightly closed
- Recommended storage period: ≤ 2 years under proper conditions
Conclusion
Optical brightener OB-1 is a high-performance fluorescent whitening agent engineered for polymers processed at elevated temperatures. With exceptional thermal stability, outstanding whitening efficiency, and broad applicability across polyesters, polyamides, and engineering plastics, OB-1 remains one of the most reliable and cost-effective choices for manufacturers seeking superior brightness and product aesthetics.
At Shandong Grand Chemical Co., Ltd., we specialize in producing and supplying a wide range of high-performance optical brighteners for plastics, coatings, detergents, and textiles.
📩 Contact us for product data sheets, samples, or technical guidance:
Email: sales@obachemical.com
WhatsApp: +86 13173009832