In the realm of specialty chemicals, certain compounds become indispensable due to their unique properties and broad applicability. CAS 1533-45-5, widely recognized as Optical Brightener OB-1 or Fluorescent Brightener 393, is one such critical material. For B2B buyers, understanding the chemical profile and market positioning of this fluorescent whitening agent is vital for making informed purchasing decisions. As a dedicated supplier and manufacturer, we aim to provide a comprehensive overview of OB-1's significance.

Chemically, OB-1 is a diphenylethylene bisbenzoxazole compound, denoted by the molecular formula C28H18N2O2. Its structure allows it to absorb ultraviolet light in the range of 340-380 nm and re-emit it as visible blue light, typically around 430-440 nm. This fluorescence effectively masks inherent yellowness in materials, resulting in a dramatically improved perceived whiteness and brightness. This phenomenon is leveraged across numerous industries, from plastics to textiles and coatings.

The primary applications of OB-1 are found in enhancing the visual appeal of polymers and synthetic fibers. Its key advantages include an exceptionally high melting point (355-360°C) and excellent thermal stability, making it suitable for high-temperature processing applications without decomposition. This is particularly important for engineering plastics and polyester fibers, where processing conditions can be demanding. Buyers often look for manufacturers that can guarantee batch-to-batch consistency in these properties.

Procurement professionals will find OB-1's compatibility with a wide range of polymers highly advantageous. It is commonly used in ABS, PS, HIPS, PA, PC, PP, EVA, and rigid PVC, as well as in polyester and nylon fibers. This versatility means that a single sourcing decision can address the needs of multiple product lines. When considering a purchase, it is important to discuss your specific polymer system with your supplier to ensure optimal dispersion and performance. The typical recommended dosage is between 0.005% and 0.2% by weight.

The market for CAS 1533-45-5 is robust, driven by the continuous demand for aesthetically superior products. Manufacturers and suppliers play a crucial role in ensuring the availability of high-purity OB-1 at competitive prices. For businesses seeking to buy this fluorescent brightener, partnering with a reputable manufacturer in China provides access to cost-effective solutions backed by stringent quality control measures. Understanding the supplier's certifications, such as REACH compliance, can also be a deciding factor.

In essence, CAS 1533-45-5, or Optical Brightener OB-1, is a high-performance chemical additive that offers significant value by enhancing the visual qualities of materials. Its unique fluorescence, combined with excellent thermal and chemical stability, makes it a go-to solution for many industries. For procurement and R&D professionals, identifying reliable sources for OB-1 is key to achieving product excellence. We invite you to contact us to explore our range of OB-1 products and discuss your specific needs.