Butylparaben occurs as colorless crystals or a white, crystalline, odorless or almost odorless, tasteless powder.
- BP: Butyl Hydroxybenzoate
- JP: Butyl Parahydroxybenzoate
- PhEur: Butyl Parahydroxybenzoate
- USP-NF: Butylparaben
Butylis parahydroxybenzoas; butyl p-hydroxybenzoate; CoSept B; 4-hydroxybenzoic acid butyl ester; Lexgard B; Nipabutyl; Tegosept B; Trisept B; Uniphen P-23; Unisept B.
Chemical Name and CAS Registry Number
Empirical Formula and Molecular Weight
Functional Category: Antimicrobial preservative.
Applications in Pharmaceutical Formulation or Technology
Butylparaben is widely used as an antimicrobial preservative in cosmetics and pharmaceutical formulations. It may be used either alone or in combination with other paraben esters or with other antimicrobial agents. In cosmetics, it is the fourth most frequently used preservative.
As a group, the parabens are effective over a wide pH range and have a broad spectrum of antimicrobial activity, although they are most effective against yeasts and molds. Owing to the poor solubility of the parabens, paraben salts, particularly the sodium salt, are frequently used in formulations. However, this may raise the pH of poorly buffered formulations.
Butylparaben sodium; ethylparaben; methylparaben; propylparaben.
Method of Manufacture
Butylparaben is prepared by esterification of p-hydroxybenzoic acid with n-butanol.