Fluorescent Brightener 52
[CAS# 91-44-1]

Identification

• Classification: Biochemical >> Amino acids and their derivatives >> Valine derivatives
• Name: Fluorescent Brightener 52
• Synonyms: 7-(Diethylamino)-4-methyl-2H-1-benzopyran-2-one; 4-Methyl-7-(diethylamino)coumarin; Coumarin 1; MDAC; C.I. 551100; Fluorescent Brightener 140; Leucophor WS
• Molecular Formula: C₁₄H₁₇NO₂
• Molecular Weight: 231.29
• CAS Registry Number: 91-44-1 (61968-71-6 / 12224-03-2)
• EC Number: 202-068-9
• SMILES: CCN(CC)C1=CC2=C(C=C1)C(=CC(=O)O2)C

Properties

• Density: 1.122
• Melting point: 70-73 °C
• Flash point: 152 °C
• Water solubility: slightly soluble

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H312-H315-H319-H332-H335-H411
• Safety Statements: P261-P264-P264+P265-P271-P273-P280-P302+P352-P304+P340-P305+P351+P338-P317-P319-P321-P332+P317-P337+P317-P362+P364-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H332
Specific target organ toxicity - single exposure	STOT SE	3	H335
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Acute toxicity	Acute Tox.	4	H302
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412

Discovery and Applications

Fluorescent Brightener 52 is a synthetic chemical compound widely used in the textile, paper, and detergent industries for its optical brightening properties. It belongs to the family of stilbene-based optical brighteners, known for their ability to absorb ultraviolet (UV) light and re-emit it as visible blue light. This effect enhances the brightness and whiteness of materials, making it a popular additive in various consumer products.

The discovery of Fluorescent Brightener 52 was part of broader research efforts to develop compounds that could counteract the yellowing of fabrics and other materials. It works by absorbing UV light in the 300–400 nm range and emitting blue light in the 420–480 nm range. This compensates for the natural yellow tint in textiles and papers, giving them a perceived brighter and whiter appearance. The development of such brighteners revolutionized industries like detergents, allowing clothes to maintain their whiteness even after multiple washes.

Fluorescent Brightener 52 is primarily used in laundry detergents, where it helps fabrics appear cleaner and brighter. In addition to its application in household cleaning products, the substance is also used in the paper industry to enhance the brightness of paper products. When added to the pulp during the paper manufacturing process, it gives paper a whiter and more vibrant finish. Similarly, in textiles, it is applied to synthetic and natural fibers to improve their optical properties.

The chemical structure of Fluorescent Brightener 52 is characterized by a stilbene backbone, which is responsible for its UV-absorbing and light-emitting properties. This structure makes it highly effective as an optical brightener, contributing to its widespread use in various commercial products. The compound is also valued for its stability under different conditions, ensuring its effectiveness across various applications.

Fluorescent Brightener 52 has become an essential component in industries that require the maintenance of brightness and visual appeal. Ongoing research continues to explore ways to improve the efficiency and environmental sustainability of optical brighteners like Fluorescent Brightener 52, given their importance in modern manufacturing processes.

References

2023. HPLC-HR-ESI-MS/MS identification of fluorescent dyes and optical brighteners and their degradation products in daylight fluorescent paints. Heritage Science, 11(1).
DOI: 10.1186/s40494-023-00993-6

2024. New 4-styrylcoumarin Derivatives as Potentials Fluorescent Labels for Biomolecules: Application in RNA-fish Probes. Applied Biochemistry and Microbiology, 60(5).
DOI: 10.1134/s000368382360286x

2023. Fabrication of a Liquid Scintillator based on 7-Diethylamino-4-Methylcoumarin for Radiation Detection. Journal of Fluorescence, 33(5).
DOI: 10.1007/s10895-023-03162-x