PIONIN (INCI: Quaternium-73) is a well-established, yellow crystalline antimicrobial active developed by Nagase Viita, with a long history of safe use in cosmetics in Japan since the 1950s. It is authorized for use in quasi-drug formulations by the Japanese Ministry of Health and Welfare.

PIONIN provides broad-spectrum antimicrobial activity effective against both gram-positive and gram-negative bacteria, including Propionibacterium acnes, making it suitable for anti-acne, anti-dandruff, and deodorant applications. It is thermally stable, maintains efficacy across a wide pH range, and is photostable when protected from light, supporting reliable preservation performance throughout a product's shelf life.

With its proven efficacy at low use concentrations and flexible compatibility with common cosmetic solvents, PIONIN offers formulators a dependable antimicrobial solution for personal care products requiring targeted preservation and skin benefit performance.