The material selection platform
Cosmetics Ingredients
The material selection platform
Cosmetics Ingredients


CAS Number 78491-02-8
Chem/IUPAC Name: 1-[1,3-bis(Hydroxymethyl)-2,5-dioxoimidazolidin-4-yl]-1,3-bis(hydroxymethyl)urea
EINECS/ELINCS No: 278-928-2
COSING REF No: 33218
Diazolidinyl Urea is a synthetic preservative that protects formulations against harmful bacteria and fungi. It works by releasing formaldehyde in the products which prevents contamination - increasing the shelf life of the cosmetic products. In its raw form, Diazolidinyl Urea appears as a fine white powder and acts as a crucial background ingredient in the beauty world. However, it has considerable risks of allergies especially when used in higher concentrations. Proper formulation is necessary for its safe use.

What is DIAZOLIDINYL UREA used for?

Diazolidinyl Urea is a widely utilized preservative in the cosmetic industry, ensuring product stability and safety. Its antimicrobial properties inhibit the growth of bacteria, yeast, and mold, extending the shelf life of various formulations, including creams, lotions, shampoos, and makeup. By preventing microbial contamination, Diazolidinyl Urea helps maintain product integrity and efficacy, preserving the quality of cosmetics over time. Despite some concerns about potential sensitivities, its effectiveness in preventing spoilage makes it a valuable ingredient in cosmetic formulations.


Diazolidinyl Urea is synthesized from two primary ingredients: allantoin and formaldehyde. Allantoin, a compound found in plants and animals, undergoes a chemical reaction with formaldehyde under alkaline conditions to produce Diazolidinyl Urea.

What does DIAZOLIDINYL UREA do in a formulation?

  • Antimicrobial
  • Preservative

Safety profile

Diazolidinyl Urea has considerable risks involved in the form of skin sensitivities like irritation and redness, especially when used in concentrations higher than 0.5%. Due to its formaldehyde-releasing nature, it can exacerbate symptoms in those sensitive to formaldehyde. Individuals with existing skin conditions or compromised skin barriers may be more susceptible to these side effects. Patch testing before use is mandated.

Technical profile

Property Values
Melting Point 157.8°C
pH 3-6
Solubility Soluble in water
Viscosity Low
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