Phenylbenzimidazole sulfonic acid

Phenylbenzimidazole sulfonic acid (CAS 27503-81-7), commonly abbreviated as PBSA, is a water-soluble UV filter used primarily in sun care and personal care formulations. Unlike oil-soluble UV absorbers, its water solubility makes it suitable for aqueous and hydrophilic systems.

This chemical is ideal for applications where broad-spectrum UVB protection is required. PBSA is a regulated UVB-filtering active in sunscreens, functioning across lotions, sprays, and gel formulations where water-phase UV protection is needed.

In pharmaceutical topical preparations, it provides photostabilization to light-sensitive active ingredients, extending product shelf life and efficacy. Personal care manufacturers incorporate it into daily moisturizers and after-sun products.

These formulations deliver UVB protection without compromising texture or transparency. It also appears in combination UV filter systems alongside UVA absorbers, where its water solubility complements oil-phase actives to achieve full-spectrum coverage.

PBSA is supplied as a white to off-white crystalline powder. It is available in cosmetic-grade and pharmaceutical-grade specifications, with purity levels typically at 98% or higher to meet regulatory requirements in sun care markets.

Suppliers commonly offer it in compliance with EU Cosmetics Regulation and equivalent international standards governing UV filter actives. The material is often tested against USP and Ph.Eur. standards to ensure safety and performance.