Fluorescent Brightening Agent 24
[CAS# 12224-02-1]

Identification

• Classification: Catalysts and additives >> Fluorescent whitening agent
• Name: Fluorescent Brightening Agent 24
• Synonyms: 2,2'-(1,2-Ethenediyl)bis[5-[[4-[bis(2-hydroxyethyl)amino]-6-[(3-sulfophenyl)amino]-1,3,5-triazin-2-yl]amino]benzenesulfonic acid sodium salt
• Molecular Formula: C₄₀H₄₀N₁₂O₁₆S₄.₄Na
• Molecular Weight: 1165.03
• CAS Registry Number: 12224-02-1
• EC Number: 235-422-6
• SMILES: C1=CC(=CC(=C1)S(=O)(=O)[O-])NC2=NC(=NC(=N2)N(CCO)CCO)NC3=CC(=C(C=C3)/C=C/C4=C(C=C(C=C4)NC5=NC(=NC(=N5)NC6=CC(=CC=C6)S(=O)(=O)[O-])N(CCO)CCO)S(=O)(=O)[O-])S(=O)(=O)[O-].[Na+].[Na+].[Na+].[Na+]

Safety Data

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319

Discovery and Applications

Fluorescent Brightening Agent 24 (FBA 24), also known as optical brightener 24, is a chemical compound developed to enhance the appearance of fabrics and materials by making them appear whiter and brighter. It belongs to the class of fluorescent whitening agents (FWAs) and works by absorbing ultraviolet (UV) light and re-emitting it as visible blue light. This process masks yellowing in materials and gives them a whiter, more vibrant appearance. FBA 24 was discovered during the mid-20th century when researchers were investigating ways to improve the whiteness of textiles without the use of bleaching agents.

One of the primary applications of Fluorescent Brightening Agent 24 is in the textile industry. It is commonly added to detergents, where it helps enhance the appearance of clothes and fabrics during the washing process. By binding to the fabric, FBA 24 enhances the material’s brightness under daylight or artificial light, providing a cleaner and fresher look. This has led to its widespread use in laundry detergents, fabric softeners, and textile treatments.

FBA 24 is also used in the paper industry to improve the brightness and whiteness of paper products. When added during the paper manufacturing process, it enhances the visual appeal of paper by counteracting the natural yellowish tint of cellulose. This makes paper appear whiter, which is particularly desirable for printing and packaging applications. Its brightening effect is highly valued in industries that require high-quality, visually appealing paper products, such as magazines, brochures, and books.

In addition to textiles and paper, Fluorescent Brightening Agent 24 is used in plastics and coatings. It improves the optical properties of polymers by making them appear brighter and more reflective under UV light. This is especially useful in packaging materials, where the brightening effect enhances the appearance of products on store shelves. Furthermore, FBA 24 is employed in the production of certain cosmetics, where it is used to enhance the appearance of the skin by reflecting light and creating a smoother, more even skin tone.

References

1993. Rapid microscopical diagnosis of deep-seated mycoses following maceration of fresh specimens and staining with optical brighteners. Mycoses.
DOI: 10.1111/j.1439-0507.1993.tb00757.x

2007. A study of peroxyoxalate-chemiluminescence of 4,4′-bis{[4,6-bis (2-hydroxyethyl)amino-1,3,5-triazin-2-yl]amino}stilbene-2,2′-disulfonic acid-disodium salt as a novel blue fluorescer. Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy.
DOI: 10.1016/j.saa.2006.03.030

1989. New fluorescence assay for the quantitation of fungi. Journal of Clinical Microbiology.
DOI: 10.1128/jcm.27.9.2003-2007.1989