Ph
Phenylbenzimidazole Sulfonic Acid
Phenylbenzimidazole Sulfonic AcidSPF filter
A water-soluble UVB sunscreen filter (Ensulizole) that gives a light, non-greasy feel — common in daily-wear lotions and serums with SPF.
What it does
Phenylbenzimidazole sulfonic acid, known as Ensulizole, is a UVB filter that absorbs the burning wavelengths of sunlight. Because it is water-soluble it formulates into light, watery textures rather than heavy creams, which is why it appears in cosmetically elegant daily SPF products. It offers little UVA protection on its own, so it is paired with other filters for broad-spectrum coverage.
Also known as
ensulizole
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