Optical Brighteners

1. Introduction 1.1. Physical Principles 1.2. Molecular Structure 1.3. History of Whitening 2. Chemistry of Technical Products 2.1. Carbocycles 2.1.1. Distyrylbenzenes 2.1.2. Distyrylbiphenyls 2.1.3. Divinylstilbenes 2.2. Triazinylaminostilbenes 2.3. Stilbenyl‐2 H ‐triazoles 2.3.1. Stilbenyl‐2 H ‐naphtho[1,2‐ d ]triazoles 2.3.2. Bis(1,2,3‐triazol‐2‐yl)stilbenes 2.4. Benzoxazoles 2.4.1. Stilbenylbenzoxazoles 2.4.2. Bis(benzoxazoles) 2.5. Furans, Benzo[ b ]furans, and Benzimidazoles 2.5.1. Bis(benzo[ b ]furan‐2‐yl)biphenyls 2.5.2. Cationic Benzimidazoles 2.6. 1,3‐Diphenyl‐2‐pyrazolines 2.7. Coumarins 2.8. Naphthalimides 2.9. 1,3,5‐Triazin‐2‐yl Derivatives 3. Commercial Forms and Brands 4. Uses 4.1. General Requirements 4.2. Textile Industry 4.3. Detergent Industry 4.4. Paper Industry 4.5. Plastics and Synthetic Fibers 4.6. Other Uses 5. Analytical Methods and Whiteness Assessment 5.1. Analytical Methods 5.2. Assessment of Whitening Effect 6. Environmental Aspects