Techniques for Creating Smooth Physical Sunscreen with Zinc Oxide and Titanium Dioxide

Question

I am formulating a cream-based physical sunscreen using the following ingredients:

Zinc Oxide
Titanium Dioxide

How can I achieve a smooth, professional texture that is not grainy and avoids leaving a white cast on the skin? Are there specific types of ingredients (such as pre-dispersed forms) or mixing techniques (like high-shear mixing) that you recommend for best results?

MySkinRecipes Expert · Accepted Answer

To achieve a smooth, non-grainy, and non-white texture in a physical sunscreen (Zinc Oxide & Titanium Dioxide), here are the key techniques and product recommendations:

1. Choose Pre-Dispersed (Liquid) Forms

The easiest way to get a professional, smooth finish without graininess is to use ingredients that are already dispersed in a liquid base. These mix easily into the oil phase of your formula.

Zinc Oxide Transparent Dispersion (C12-15 alkyl benzoate Base): A nano-sized zinc oxide dispersion that provides high transparency and is easy to incorporate.
Titanium Dioxide Transparent (10nm, C12-15 Alkyl Benzoate Base): A very small particle size dispersion that prevents a white cast.

2. Use Surface-Treated Powders (EasyDisperse™)

If you prefer using powder, choose versions that have been surface-treated to disperse easily in oil or silicone.

Zinc Oxide 200nm EasyDisperse™: This powder is coated with silicone, making it much easier to distribute evenly compared to standard zinc oxide.

3. Key Mixing Techniques

Pre-mixing (Slurry): If using powders, never add them directly to the cream base. Mix the powder with an emollient or silicone (like Cyclomethicone) in a 1:1 ratio first. Stir until it becomes a smooth paste (slurry) before adding it to the rest of the formula.
Use Dispersing Agents: Adding an ester like LipidSoft™ SPF helps wet the particles and ensures they stay separated, preventing clumping and improving spreadability.
High-Shear Mixing: Using a high-speed mixer or homogenizer is highly recommended to break down any remaining aggregates for a perfectly smooth texture.

4. The Simplest Option: Ready-to-Use Base

For a guaranteed smooth texture and high SPF without the complexity of dispersing minerals yourself, you can use a pre-made base:

Pure Physical Sunscreen (SPF50+, PA3+, Water-in-Oil, Non-White): This is a finished sunscreen base that you can customize with your own active ingredients. It is designed to be lightweight and non-whitening.