Diazolidinyl urea is an antimicrobial preservative used in cosmetics. It is chemically related to imidazolidinyl urea which is used in the same way. Diazolidinyl urea acts as a formaldehyde releaser. It is used in many cosmetics, skin care products, shampoos and conditioners, as well as a wide range of products including bubble baths, baby wipes and household detergents. Diazolidinyl urea is found in the commercially available preservative Germaben. Commercial diazolidinyl urea is a mixture of different formaldehyde addition products including polymers.