Optical Brightener OB-1,  also known as Fluorescent Brightener 393,  OBA 393, Optical Brightener 393,  or Fluorescent Brightener OB-1, is an excellent oxazole type whitening agent that is particularly suitable for particularly resistant to high temperatures and is suitable for whitening various plastics and plastic products which undergo forming and processing  at high temperatures. It is also suitable for whitening polyester fibers and blending fabrics of polyester, cotton, and other fibers.

BoldChem supplies high quality Optical Brightener OB-1 (CAS No. 1533-45-5) with very competitive price.

Technical Specs of Optical Brightener OB-1

Chemical Name:  Fluorescent Brightener 393
CAS No:  1533-45-5
Molecular Formula:  C28H18N2O2
Molecular Weight:  414.45
Appearance:  bright yellow powder
Melting Point:  >300°C(lit.)
Purity:   ≥99.0%
Volatiles:  ≤0.2%
Ash:  ≤0.1%

Properties of Optical Brightener OB-1

Optical Brightener OB1 is insoluble in water, but soluble in high boiling point organic solvents such as benzene dichloride. It has high whitening strength, strong fluorescence, good resistance of heat, light, migration, and chlorine bleaching resistance.

OBA 393 can appear green or yellow phase. The green phase emits blue fluorescent light, while the yellow phase is blue-violet light. Green phase one is used more commonly, as its whitening effect is better. However, due to its good whitening effect, the dosage must be controlled to avoid excessive use to appear too much of the whitening agent’s color.

Fluorescent Brightener OB-1 is currently the highest temperature resistance whitener among all optical brightener varieties, making it the best choice to whiten products that need to be processed at high temperature.

Applications of Optical Brightener OB-1

Optical brightener OB-1 is particularly resistant to high temperatures and is suitable for whitening various plastics and plastic products which undergo forming and processing at high temperatures. It is also suitable for whitening polyester fibers and blending fabrics of polyester, cotton, and other fibers. Fluorescent Brightener OB-1 can also be used for whitening plastics such as ABS, PS, HIPS, PA, PC, PP, EVA, and hard PVC. It can also significantly whiten nylon fibers, nylon, and polyester.

Adding Optical brightener OB1 to the recycled polyester fiber waste, bottle material, and chips, the recycled material will appear whiter and the color will become more consistent among different recycled materials.

Fluorescent Brightener OB-1 is the only one brightener that can withstand high temperatures up to 300 degrees Celsius, which makes it applicable to almost all plastics. However, it has a poor stability. Under the same addition, temperature and humidity, Optical brightener OB-1 has a larger migration and precipitation, which means plastic products are more prone to yellowing in the later stage. So in situations where low yellowing is required, such as EVA footwear products, it is necessary to choose Optical brightener KCB which has a good stability.

Packaging and Storage

Optical Brightener OB-1 is packed 20 kgs or 25 kgs per fiber drum lined with PE bag, and stored in cool and dry place without direct sunlight. Shelf life of it is at least 2 years with proper packaging and storage.