2,2',4,4'-Tetrahydroxybenzophenone
[CAS# 131-55-5]

Identification

• Classification: Catalysts and additives >> UV absorber
• Name: 2,2',4,4'-Tetrahydroxybenzophenone
• Synonyms: Di(2,4-dihydroxyphenyl)methanone; Bis(2,4-dihydroxyphenyl)methanone
• Molecular Formula: C₁₃H₁₀O₅
• Molecular Weight: 246.22
• CAS Registry Number: 131-55-5
• EC Number: 205-028-9
• SMILES: C1=CC(=C(C=C1O)O)C(=O)C2=C(C=C(C=C2)O)O

Properties

• Density: 1.5±0.1 g/cm³, Calc.^*, 1.216 g/mL (Expl.)
• Melting point: 198-200 ºC (Expl.)
• Index of Refraction: 1.718, Calc.^*
• Boiling Point: 531.2±25.0 ºC (760 mmHg), Calc.^*
• Flash Point: 289.1±19.7 ºC, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H302-H315-H317-H319-H335-H412
• Precautionary Statements: P261-P264-P264+P265-P270-P271-P272-P273-P280-P301+P317-P302+P352-P304+P340-P305+P351+P338-P319-P321-P330-P332+P317-P333+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412

Discovory and Applicatios

2,2',4,4'-Tetrahydroxybenzophenone, often referred to as THBP, is an organic compound recognized for its strong ultraviolet (UV) absorption properties. This substance, part of the benzophenone family, features four hydroxyl groups attached to its benzophenone core, enabling it to efficiently absorb UV radiation and protect materials from photodegradation. Its development was motivated by the growing need for effective UV stabilizers in various industries during the mid-20th century.

THBP was discovered during studies of benzophenone derivatives aimed at enhancing UV protection capabilities. Its chemical structure, with hydroxyl groups positioned strategically, enables the compound to absorb UV light and dissipate the energy as heat, preventing damage to surrounding materials. This property, coupled with its chemical stability, made THBP a promising candidate for use in polymers, coatings, and personal care products.

The primary application of 2,2',4,4'-Tetrahydroxybenzophenone is as a UV absorber. It is widely used in plastic materials, such as polycarbonates and polyesters, where it protects against discoloration, brittleness, and loss of mechanical strength caused by sunlight exposure. In coatings, THBP helps preserve the gloss, color, and durability of paints and varnishes, particularly those used in outdoor environments. Additionally, its incorporation into adhesives and sealants enhances their longevity under UV-rich conditions.

Another significant use of THBP is in the formulation of sunscreens and personal care products. Its ability to absorb UV radiation makes it an effective ingredient in protecting human skin from harmful UV-A and UV-B rays. The compound is also employed in specialty applications, such as stabilizing photographic films and protecting sensitive optical materials from UV damage.

The discovery and implementation of 2,2',4,4'-Tetrahydroxybenzophenone have significantly advanced the fields of material science and UV stabilization. Its versatility and efficacy underscore its importance in developing durable, long-lasting products across various sectors.