Quaternium-15

Quaternium-15 (CAS 4080-31-3), also sold under trade names Dowicil 75, Dowicil 100, Dowco 184, Dowicide Q, and Cinartc 200, is a quaternary ammonium chloride compound that functions as a formaldehyde-releasing preservative. It carries no assigned E-code and is classified under the amines category.

In personal care formulations, Quaternium-15 inhibits microbial growth in rinse-off and leave-on products by releasing formaldehyde at controlled rates, disrupting bacterial and fungal cell function. It is also applied in water treatment systems and industrial coatings to prevent biofilm formation and microbial contamination during storage and application.

Quaternium-15 is supplied as a solid and is subject to REACH registration requirements within the EU. In cosmetic applications, it falls under Annex V of the EU Cosmetics Regulation with defined concentration limits. Procurement teams should verify current regulatory status, as restrictions on formaldehyde-releasing preservatives continue to evolve across jurisdictions.