White powder. Highly soluble, hygroscopic.
Imidazolidinyl urea kills Gram-negative bacteria. It acts synergistically with the parabens to provide a broad-spectrum antibiotic effective against molds, yeast, and bacteria.
The combination of the two is the most widely used preservative in cosmetics.
It works by releasing formaldehyde into the product, like the related preservative DMDM hydantoin.
Imidazolidinyl urea: InChI=1/C11H16N8O8/c20-2-18-4(6(22)16-10(18)26)14-8(24)12-1-13-9(25)15-5-7(23)17-11(27)19(5)3-21/h4-5,20-21H,1-3H2,(H2,12,14,24)(H2,13,15,25)(H,16,22,26)(H,17,23,27)/f/h12-17H
allantoin: InChI=1/C4H6N4O3/c5-3(10)6-1-2(9)8-4(11)7-1/h1H,(H3,5,6,10)(H2,7,8,9,11)/f/h6-8H,5H2
DMDM Hydantoin: InChI=1/C7H12N2O4/c1-7(2)5(12)8(3-10)6(13)9(7)4-11/h10-11H,3-4H2,1-2H3