Organic Acids
REACH
4-hydroxybenzoic acid
CAS Number
99-96-7
EC Number
202-804-9
FEMA Number
FEMA 3986
Abbreviation
4-HBA
What is 4-hydroxybenzoic acid?
4-Hydroxybenzoic acid (CAS 99-96-7), also known as p-salicylic acid and abbreviated as 4-HBA, is the primary precursor in the synthesis of paraben preservatives used in food, pharmaceutical, and cosmetic manufacturing.
Where is 4-hydroxybenzoic acid used?
- Cosmetics and personal care: preservative and UV stabilizer in creams, lotions, and sunscreen formulations
- Pharmaceuticals: synthetic building block for paraben-based excipients and preservative in topical and oral dosage forms
- Food: flavoring and preservation under FEMA 3986 in packaged goods
- Antimicrobial agent and antioxidant stabilizer
- Key intermediate for methyl, ethyl, propyl, and butyl paraben esters
- In adhesives and polymer systems it appears where oxidative stability is required.
Commercial specifications
- Standard grades: technical, food-grade, pharmaceutical-grade meeting USP, BP, and Ph. Eur. specifications
- Packaging: bulk bags and smaller quantities
Other Names (Synonyms)
Paraben-acid|p-salicylic acid|p-Salicylate|P-Hydroxybenzoic Acid|p-Hydroxybenzoate|p-Carboxyphenol|4-Hydroxy-benzoesaeure|4-Hydroxy-benzoate|4-HBA
What are the physical properties of 4-hydroxybenzoic acid?
Melting Point 214.5 °C
Boiling Point >400 °C
Density 1.46 g/cm³ @ Temp: 25 °C
Flash Point 199 °C
Appearance White to ivory crystalline powder
Color White to ivory
Odor at 100.00 %. phenolic nutty
Form Crystalline Powder
Water Solubility 5 g/L (20 ºC)
Vapor Pressure 0Pa at 20℃
Refractive Index 1.4600 (estimate)
pH 3.3 (1g/l, H2O, 20℃)
Log P 0.878 at 22℃
How is 4-hydroxybenzoic acid classified and handled safely? Learn More
Danger
GHS05· Corrosive GHS07· Irritant
Hazard Statements
H315 Causes skin irritation
H318 Causes serious eye damage
H319 Causes serious eye irritation
H335 May cause respiratory irritation
Precautionary Statements
P261 Avoid breathing dust/fume/gas/mist/vapours/spray.
P264 Wash … thoroughly after handling.
P271 Use only outdoors or in a well-ventilated area.
P280 Wear protective gloves/protective clothing/eye protection/face protection.
Which trade and regulatory codes apply to 4-hydroxybenzoic acid?
HS Code 29182930
WGK (Germany) 1