Ethyl 4-(dimethylamino)benzoate (EDB) is a benzoate ester carrying a strong electron-donating dimethylamino group at the para-position. The compound exhibits intense UV-A absorption (λmax 308–311 nm, ε ≈ 2.7×10⁴ L mol⁻¹ cm⁻¹) and is practically insoluble in water (< 0.5 g L⁻¹ at 25 °C), freely soluble in ethanol, chloroform, ethyl acetate and most cosmetic oils. It functions as a highly efficient UV-A filter and as a co-initiator/synergist in visible-light or UV-curable systems. Commercial material is supplied at ≥ 99 % purity and remains stable for ≥ 2 years when stored at room temperature in tightly closed containers away from light.
Key Physicochemical Data:
Melting point: 63–66 °C (lit.)
Boiling point: 190–191 °C / 14 mmHg (lit.)
Density: 1.06 g cm⁻³ (25 °C)
Flash point: 115 °C (closed cup, predicted)
Log P (octanol/water): 3.2 (predicted)
Vapour pressure: 0.59 Pa at 25 °C
Typical Uses:
UV-A sunscreen agent and photostabiliser in broad-spectrum sun-care and daily-care formulations.
Co-initiator/synergist with ITX, 907 or camphorquinone for UV-curable inks, nail gels, dental resins and screen-printing varnishes.
Intermediate for lipophilic UV-absorbing monomers and fragrance encapsulation systems.
Quality Specification (Commercial Grade):
Purity (HPLC): ≥ 99 %
Water content (KF): ≤ 0.3 %
Free acid (as 4-dimethylaminobenzoic acid): ≤ 0.2 %
Residue on ignition: ≤ 0.1 %
Heavy metals: ≤ 20 ppm
Hazard Statement:
Causes skin and eye irritation (H315 + H319). Avoid inhalation of dust; use gloves, goggles and adequate ventilation. Store in a cool, dry place away from oxidants and strong acids. SDS available on request.
