Chemical name:  2,2'-(1,2-Ethenediyldi-4,1-phenylene)bisbenzoxazole CAS No.:1533-45-5                                Molecular formula: C28H18N2O2 Molecular weight: 414.45                                                                                                         Appearance: Yellow – green powder Assay, %: ≥98.5 Melting point, ℃: 355 – 361 Volatility, %: ≤0.5 Ash, %: ≤0.5 Particle size: pass 100 mesh                                                                    Optical Brightener OB-1 is especially resistant to high temperature, and is mainly used for whitening by hot melt padding. It is suitable for whitening of polyester fiber and whitening of polyester and cotton and other fiber blended fabrics. The product can also be used for plastic whitening of ABS, PS, HIPS, PA, PC, PP, EVA and rigid PVC. The addition of OB-1 to nylon fiber, nylon and polyester will also significantly improve whiteness. After adding OB-1 to recycled polyester fiber waste, bottle stock and chips, the recycled material will appear whiter and the color will become more consistent in different recycled materials.   1,It is suitable for whitening of chemical fiber such as polyester fiber, nylon fiber and polypropylene fiber. 2, Suitable polypropylene plastic, rigid PVC, ABS, EVA, polystyrene, polycarbonate or the like whitening and brightening. 3. It is suitable for the conventional polymerization of polyester and nylon. 4, Especially suitable for whitening of plastic products molded at high temperature.  info at hhochem. com