Product name: Imidazolidinyl Urea
CAS: 39236-46-9
Molecular formula: C11H16N8O8
Molecular weight: 388.29
Description: Imidazolidinyl urea is an antimicrobial preservative used in cosmetics[citation needed]. It is chemically related to diazolidinyl urea which is used in the same way. Imidazolidinyl urea acts as a formaldehyde releaser.

Some people have a contact allergy to imidazolidinyl urea causing dermatitis. Such people are often also allergic to diazolidinyl urea.

Imidazolidinyl urea is produced by the chemical reaction of allantoin and formaldehyde in the presence of sodium hydroxide solution and heat. Commercial imidazolidinyl urea is a mixture of different formaldehyde addition products including polymers.