Diazolidinyl Urea: Properties and Cosmetic Applications

What Is Diazolidinyl Urea?

Diazolidinyl Urea is primarily an antibacterial preservative, with activity against moulds but relatively weak anti-yeast activity. It has been widely used in cosmetic formulations since its introduction in the 1980s and is classified as a formaldehyde donor.

It is highly water-soluble and should be added to formulations at temperatures below 40°C to minimise decomposition. It remains active across a broad pH range of approximately pH 3–9.

Key Properties of Diazolidinyl Urea

Antibacterial Activity
Its primary preservative activity is directed against bacteria, with additional activity against moulds.

Water Solubility
Its high water solubility makes it suitable for aqueous cosmetic formulations.

Broad pH Range
Diazolidinyl Urea retains its preservative activity over approximately pH 3–9.

Heat Sensitivity
It should be incorporated below 40°C to reduce the risk of decomposition.

Cosmetic Applications

Diazolidinyl Urea is used as a preservative in a wide range of cosmetic formulations. The typical use concentration stated by A&T Formulation is 0.1–0.3%. Its use is permitted in many territories, subject to applicable regulatory restrictions.

Ingredient Information

INCI: Diazolidinyl Urea
CAS: 78491-02-8
EINECS/EC: 278-928-2

References

Cosmetic Formulation Principles and Practice – Heather A.E. Benson, Michael S. Roberts, Vânia Rodrigues Leite-Silva, Kenneth A. Walters.

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