Sodium formaldehyde bisulfite

Sodium hydroxymethanesulfonate, also known as Sodium formaldehyde bisulfite (bisulphite), used as a preservative in cosmetic compositions. The sodium hydroxymethane sulfonate is used to improve the color stability of rosin resins and it has properties of both formaldehyde and sodium bisulfite. It is typically present in an amount of from 0.05% to 5.0%, preferably about 0.25%, based on the weight of the rosin resin. Sodium hydroxymethane sulfonate, also known chemically as sodium formaldehyde bisulfite, NaCH3 OSO3, is a white, water-soluble rather inexpensive powder which forms colorless and odorless solutions. Under alkaline conditions this compound is believed to slowly hydrolyze into formaldehyde and sodium bisulfite which by their presence render the desired antibacterial and antioxidant preservative properties, respectively.