IPBC (3-Iodo-2-Propynyl Butylcarbamate) Cas No: 55406-53-6 is a member of the carbamate family of biocides. IPBC is an effective fungicide at very low concentrations in cosmetic and other products, and has shown very low sensitivity in humans tested with this preservative. IPBC was approved in 1996 for use up to 0.1% concentrations in topical products and cosmetics. However, this preservative is mostly found in cosmetics at about one-eighth that level. ZXCHEM GROUP