Role of Titanium Dioxide and Zinc Oxide in Your Formula

Based on your goal to create a high-coverage, oil-controlling foundation with SPF 50 PA+++, and your plan to use SPF Protect Ultra II at 15%, here's how Titanium Dioxide and Zinc Oxide fit in:

You are correct that using SPF Protect Ultra II at 15% can provide SPF 50 PA+++. However, Titanium Dioxide and Zinc Oxide offer benefits beyond just contributing to the SPF/PA value, especially in a foundation formula focused on coverage and oil control.

• Titanium Dioxide: While it is a physical sunscreen filter protecting against UVA and UVB rays, certain types of Titanium Dioxide are primarily used as pigments in makeup products like foundation. They are essential for providing coverage and adjusting the shade of the product. If you want a foundation with good coverage, incorporating a suitable cosmetic-grade Titanium Dioxide is necessary, regardless of the SPF contribution from other ingredients. Examples include Titanium Dioxide 250nm Pigment or Titanium Dioxide 400nm WaterProof™ (Super Coverage).
• Zinc Oxide: This is another physical sunscreen filter offering broad-spectrum protection, particularly effective against long-wave UVA. Additionally, Zinc Oxide is known for its oil-absorbing and skin-soothing properties, which are highly beneficial in a foundation designed to control shine. Using a suitable Zinc Oxide, such as Zinc Oxide 35nm Liquid or Zinc Oxide Transparent Dispersion, can help achieve the desired matte finish and oil control for your foundation.

In summary, while SPF Protect Ultra II handles the primary SPF/PA requirement using chemical filters, adding Titanium Dioxide is crucial for the coverage aspect of your foundation, and Zinc Oxide is valuable for enhancing broad-spectrum UV protection and providing oil control. Therefore, incorporating appropriate types of both Titanium Dioxide and Zinc Oxide is highly recommended to achieve all the desired properties of your foundation formula.