Abstract: The main role of Bronopol(CAS: 52-51-7) as a cosmetic preservative is to prevent the reproduction of bacteria, fungi and other microorganisms, thereby extending the service life of the product. In addition, Bronopol as a cosmetic preservative can also prevent cosmetics from deteriorating during use, ensuring the stability and safety of the product.

Keywords: Bronopol; BNP; C3H6BrNO4; preservative; biocide; CAS 52-51-7

1.Physicochemical property

Bronopol is a white crystalline powder at room temperature, odorless, tasteless, easily soluble in water, ethanol, propylene glycol, but difficult to dissolve in chloroform, acetone, benzene, etc.

Molecular formula: C3H6BrNO4

Active ingredient: ≥99%

CAS No. : 52-51-7

2.Advantages of bronopol as a cosmetic preservative

2.1 High efficiency. Bronopol has broad-spectrum antibacterial activity, and can inhibit the growth of most bacteria at 25ppm concentration, and has better effect on Gram-negative bacteria and various types of pseudomonas.

2.2 Low consumption and low price. In cosmetics, the amount of bronopol is generally 0.01~0.05%, which is one-tenth of the commonly used preservative paraben esters in cosmetics, and the use cost is more than half cheaper than paraben vinegar.

2.3 Good compatibility. Nutrients such as protein and various cationic, anionic and non-ionic surfactants did not affect the bacteriostatic effect of bronopol.

2.4 Suitable pH range. Bronopol is effective in PH4 ~ 9, that is, it can maintain strong bacteriostatic effect after the addition of bronopol in weak acidic, neutral and alkaline environment.

2.5 Good water solubility, easy to use. Bronopol is easily dissolved in water and has a solubility of 25g in water at25℃, making it extremely convenient to use.

3.Precautions for the use of bronopol as a cosmetic preservative

3.1 The use of bronopol as a cosmetic preservative should be strictly controlled, as high concentrations can have negative effects on the skin. According to relevant regulations, the preservative content in cosmetics cannot exceed 0.5%.

3.2 When bronopol is used as a cosmetic preservative, attention should be paid to the concentration and application method to ensure bactericidal effect and avoid adverse effects on the environment.

3.3 When using bronopol, protective equipment such as protective clothing, gloves and glasses should be worn to avoid contact with skin and eyes, and it is recommended that bronopol be used in a well-ventilated environment.

3.4 During the use of bronopol, direct spraying on humans or animals should be avoided, and attention should be paid to avoiding ingestion and respiratory tract contact.

3.5Bronopol should be kept in a dry, cool and well-ventilated place, away from direct sunlight and high temperature.