To modify your sunscreen formula to achieve SPF50 PA++++, minimize white cast, improve spreadability, and be non-comedogenic, consider the following adjustments:

Sunscreen Active Ingredients

• Replace the current Titanium Dioxide 15nm Liquid (Gloss) with transparent or nano-dispersions of both Titanium Dioxide and Zinc Oxide. Using both physical filters is crucial for broad-spectrum protection (UVA and UVB) required for SPF50 PA++++.
• Transparent/nano dispersions help significantly reduce the white cast typically associated with physical sunscreens.
• The specific grades and percentages of Titanium Dioxide and Zinc Oxide dispersions will need to be optimized through testing to reach SPF50 PA++++ and ensure minimal white cast and good feel.

Emollients and Texture

• The choice of emollients is key for spreadability and a non-greasy, non-comedogenic feel. Consider using emollients specifically designed for sunscreen formulations, such as LipidSoft™ SPF, which can help disperse the UV filters and improve the overall texture.
• Adjust the total emollient content to achieve the desired spreadability and skin feel without being heavy or occlusive.

Other Beneficial Ingredients

• Ingredients like Mild Preserved Eco™, MSH White™, Myristyl Nicotinate, Natural Bisabolol, and Sugar-Film™ (Inulin) can generally be kept in the formula as they provide additional benefits (preservation, whitening, skin conditioning, soothing, moisturizing/film-forming) and do not directly interfere with the UV protection or white cast issues, assuming compatibility with the chosen base and emulsion type.

Formulation Type

• Consider formulating as an oil-in-water (O/W) emulsion, which often provides a lighter, less greasy feel compared to water-in-oil (W/O) emulsions, contributing to better spreadability and a less occlusive feel. This depends on the compatibility of your chosen transparent UV filter dispersions.

Achieving the desired SPF/PA level and aesthetic properties requires careful selection of specific ingredient grades and precise formulation techniques. It is highly recommended to perform stability and SPF/PA efficacy testing on the final formula.