---
title: "What is a Sunscreen made of?"
description: "UV filters — mineral, chemical or both — suspended in an emulsion whose job is to hold them in an even film. Every component, the material it uses, and the constrain"
url: https://atoneplace.net/made-of/sunscreen/
site: "At One Place"
---

# What is a Sunscreen made of?

**What is a Sunscreen made of?: UV filters — mineral, chemical or both — suspended in an emulsion whose job is to hold them in an even film.**

Sunscreen is regulated as an over-the-counter drug in the US and as a cosmetic in the EU, Japan and Australia, and that single administrative difference is why European and Asian sunscreens have access to modern broad-spectrum filters that have been waiting for US approval for two decades. SPF measures protection against UVB and sunburn only; UVA protection is shown separately by a PA rating or a circled UVA mark. Real-world protection is usually far below the labelled figure because almost nobody applies the 2 mg/cm² used in testing — about a teaspoon for the face and neck — so reapplying every two hours matters more than chasing a higher SPF number.

## Component by component

*Every material is a choice, and the third column is the constraint that drove it.*

| Part | Material | Why that material |
| --- | --- | --- |
| mineral filters | zinc oxide and titanium dioxide | They absorb and scatter across the UV range, are photostable, and are the only filters generally recognised as safe and effective by the US FDA. |
| organic filters | avobenzone, octocrylene, homosalate, octisalate, and outside the US, Tinosorb and Uvinul filters | They absorb specific UV wavelengths and feel far lighter on the skin than mineral filters at the same protection level. |
| stabiliser | octocrylene or a dedicated photostabiliser paired with avobenzone | Avobenzone is the main UVA filter available in the US and degrades in sunlight within an hour unless it is stabilised. |
| emulsion base | water, oils, emulsifiers and thickeners | Protection depends on an even, thick film; the base decides whether it spreads evenly and stays put in sweat and water. |
| film formers | polymers that resist water and rub-off | Water resistance is tested for 40 or 80 minutes; nothing is waterproof, and the label is not allowed to say so. |

## Other around the house objects

- [Banknote](https://atoneplace.net/made-of/banknote/) — Cotton and linen rag paper, or polymer film — never wood pulp, which is why notes survive the wash.
- [Lego brick](https://atoneplace.net/made-of/lego-brick/) — ABS plastic moulded to a tolerance of about ten micrometres — the tightness of the fit is the whole product.
- [Soap](https://atoneplace.net/made-of/soap/) — Fats reacted with lye to make fatty acid salts — and most modern "beauty bars" are not soap at all.
- [Toothpaste](https://atoneplace.net/made-of/toothpaste/) — Mostly abrasive and humectant, with a detergent for foam — the active ingredient is about 0.15% fluoride.
- [Coin](https://atoneplace.net/made-of/coin/) — Base-metal alloys chosen for wear and cost — most modern "silver" coins are copper-nickel and most "copper" ones are plated steel or zinc.
- [Credit card](https://atoneplace.net/made-of/credit-card/) — Laminated PVC sheets 0.76 mm thick, carrying a silicon chip in epoxy and a copper antenna coil.
- [Candle](https://atoneplace.net/made-of/candle/) — Wax that is really a fuel, and a braided cotton wick that acts as a pump rather than as the thing burning.
- [Lipstick](https://atoneplace.net/made-of/lipstick/) — Castor oil carrying pigment, set into a stick with waxes — the oil is the workhorse, not the colour.
- [Shampoo](https://atoneplace.net/made-of/shampoo/) — Three-quarters water, a primary detergent, a milder secondary one, salt to thicken, and silicone to make hair feel smooth.
- [Balloon](https://atoneplace.net/made-of/balloon/) — Party balloons are dipped natural rubber latex; foil balloons are metallised plastic film and are not rubber at all.
- [Deodorant](https://atoneplace.net/made-of/deodorant/) — Deodorant kills the bacteria that cause the smell; antiperspirant uses aluminium salts to plug the sweat duct. Different products.
- [Toothbrush](https://atoneplace.net/made-of/toothbrush/) — Nylon filaments stapled into a polypropylene handle with a wire — three plastics that cannot be separated for recycling.

## Common questions

### What is a Sunscreen made of?

UV filters — mineral, chemical or both — suspended in an emulsion whose job is to hold them in an even film.

### What is the mineral filters of a Sunscreen made of?

Zinc oxide and titanium dioxide. They absorb and scatter across the UV range, are photostable, and are the only filters generally recognised as safe and effective by the US FDA.

### What is the organic filters of a Sunscreen made of?

Avobenzone, octocrylene, homosalate, octisalate, and outside the US, Tinosorb and Uvinul filters. They absorb specific UV wavelengths and feel far lighter on the skin than mineral filters at the same protection level.

## Related pages

- [Banknote](https://atoneplace.net/made-of/banknote/)
- [Lego brick](https://atoneplace.net/made-of/lego-brick/)
- [Soap](https://atoneplace.net/made-of/soap/)
- [Toothpaste](https://atoneplace.net/made-of/toothpaste/)
- [Coin](https://atoneplace.net/made-of/coin/)
- [Credit card](https://atoneplace.net/made-of/credit-card/)
- [Candle](https://atoneplace.net/made-of/candle/)
- [Lipstick](https://atoneplace.net/made-of/lipstick/)
- [Pencil](https://atoneplace.net/made-of/pencil/)
- [Tennis ball](https://atoneplace.net/made-of/tennis-ball/)
- [Golf ball](https://atoneplace.net/made-of/golf-ball/)
- [Paper](https://atoneplace.net/made-of/paper/)
- [Glass](https://atoneplace.net/made-of/glass/)
- [Soccer ball](https://atoneplace.net/made-of/soccer-ball/)

## Sources

- Official vendor product documentation — At One Place (/about/)