Sunscreen Formulation Feedback for Outdoor Sports

This is a good starting formula with a solid base of physical and chemical sunscreen filters, emollients, and beneficial extracts. To achieve SPF50+ PA++++ and ensure suitability for outdoor sports activities (requiring high water and sweat resistance), consider the following adjustments:

Key Considerations & Recommendations

1. Sunscreen Active Concentration: The current levels of Zinc Oxide 35nm Liquid (15%), Titanium Dioxide 15nm Liquid (10%), and SPF Protect Ultra™ II (10%) provide a good foundation for broad-spectrum protection. To confidently reach SPF50+ PA++++, you may need to slightly increase the concentration of one or more of these sunscreen actives. The exact levels required would need to be determined through testing.

2. Enhance Water Resistance: For outdoor sports, robust water and sweat resistance is crucial. Your formula includes WaterGuard™ Lite, Vinyl Film, and Polyethylene Wax, which contribute to film formation and waterproofing. However, WaterGuard™ Lite is described as providing a thin film that is "not very waterproof." To significantly improve water resistance, consider increasing the concentration of Polyethylene Wax, which is known to help make formulas more waterproof and boost SPF. Alternatively, you could explore other film-forming polymers specifically designed for high water resistance in sunscreens.

3. Texture and Feel: The formula includes several ingredients like Cyclomethicone, Silicone Gel (Ultra Clear), QuikBlur™, LipidSoft™ Moist, and Fractionated Coconut Oil that contribute to a light, smooth, and non-greasy feel. SelectSorb™ is also included for oil absorption, which is beneficial for sports activities. While increasing film formers can sometimes impact texture, the current combination seems well-balanced. Monitor the texture and feel if you increase the concentration of Polyethylene Wax or add other film formers.

4. Stability: Ensure the formula remains stable after any adjustments, particularly the dispersion of the physical filters (Zinc Oxide 35nm Liquid and Titanium Dioxide 15nm Liquid) and the overall emulsion stability using Warp Cream Maker™. Polyhydroxystearic acid is a good addition to help with pigment dispersion.

5. Testing: To confirm that the modified formula achieves SPF50+ PA++++ and the desired level of water resistance for outdoor sports, it is essential to perform laboratory testing.

Summary of Potential Modifications

• Slightly increase the percentage of Zinc Oxide 35nm Liquid, Titanium Dioxide 15nm Liquid, and/or SPF Protect Ultra™ II.
• Increase the percentage of Polyethylene Wax or use a stronger film-forming polymer to enhance water resistance.

By optimizing the sunscreen active concentrations and strengthening the waterproof film, you can create a high-performance sunscreen suitable for outdoor sports activities.

(Thank you)