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Polyisobutene

What Polyisobutene is & what it does

A clear, conditioning emollient that gives a smooth, glossy, water-resistant film. It improves shine and wear.

What is Polyisobutene and what does it do in sunscreen?

Polyisobutene is a clear, conditioning emollient that forms a smooth, glossy, water-resistant film on the skin. In sunscreen it improves shine, wear, and how long the product stays put, which is useful for water resistance and a fresh-looking finish. It also helps give a cushiony, slip feel during application. You will often see it in sprays, gels, and long-wearing formulas.

Is Polyisobutene safe?

Yes. Polyisobutene is a stable, inert film former that sits on the surface of the skin and is well tolerated by most people. It does not penetrate or react with the skin, and it has a solid track record across cosmetics and sun care. It is generally a low-irritation ingredient suitable even for sensitive skin.

Does Polyisobutene clog pores?

Generally no. It is not flagged as comedogenic. Polyisobutene forms a film on top of the skin rather than soaking in, and it is not a heavy plant oil or butter of the type usually linked to clogged pores. If you are breakout-prone, the richer oils and waxes elsewhere in a formula are a more likely cause.

Is Polyisobutene natural or synthetic?

It is synthetic. Polyisobutene is a polymer made by joining many isobutene units in a lab, which gives it the clear, glossy, water-resistant character it is valued for. It does not occur in nature, and that is normal for film formers designed for long wear and water resistance.

What is Polyisobutene on an ingredient list (INCI)?

Polyisobutene is the INCI name on the label, and you may also see the hydrogenated version, Hydrogenated Polyisobutene, which serves a similar emollient and film-forming role. It usually appears in the middle of the ingredient list, among the other emollients and texture agents.

Sunscreens with Polyisobutene

We rate 241 sunscreens that contain it, showing the top 10 by overall score:

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