Zinc oxide in sunscreen and skincare
Zinc oxide is one of the few UV filters that covers the full UVA and UVB range while remaining acceptable in sensitive-skin formulations. Getting it into a product that feels good is the harder part.
Why formulators choose zinc oxide
Zinc oxide attenuates across both UVA and UVB, which matters for products claiming broad-spectrum protection. Unlike organic filters, it does not penetrate the skin, and it is not associated with the sensitisation concerns that limit some chemical absorbers. It also functions as a physical barrier, which is why it appears in formulations targeting reactive or compromised skin.
The formulation problem
Uncoated zinc oxide at the loading needed for meaningful SPF leaves a visible white cast and can feel heavy. Two levers address this: reducing particle size to the range where scattering drops, and coating the particle surface to control photocatalytic activity and improve dispersion. The first improves appearance, the second improves stability — and they trade off against each other.
What we supply
A cosmetic UV filter grade with controlled D50 for appearance, and a surface-coated grade where photocatalytic interaction with other actives is a concern. Both are specified by particle size distribution, coating type, and per-lot certificate of analysis.
Parameters specified per grade
Parameters marked grade-specific are fixed when the grade is defined, and are issued with the technical data sheet.
| Parameter | Value |
|---|---|
| ZnO content | Grade-specific |
| Particle size D50 | Grade-specific |
| Coating | Grade-specific |
| Photocatalytic activity | Grade-specific |
| Heavy metals | Grade-specific |
| Microbiological limits | Grade-specific |
Full specification is issued with the technical data sheet.Request the TDS for the grade you are evaluating.