Sunscreen Formulation Review

Thank you for providing your proposed sunscreen formula. It contains a good selection of UV filters aimed at achieving broad-spectrum protection (UVA/UVB) and a high PA++++ rating, along with beneficial skincare ingredients.

Here is an evaluation of the formula and some points to consider:

Feasibility and Potential Adjustments

1. UV Filter Combination: The combination of Drometrizole Trisiloxane, Ethylhexyl Triazone, BEMT, DHHB, and Bisoctrizole is effective for achieving high SPF and PA++++. These filters cover a wide range of UV wavelengths.
2. Reef Safe: Your formula uses only organic UV filters. By commonly accepted definitions, a "Reef Safe" sunscreen typically relies on mineral filters like Zinc Oxide and Titanium Dioxide. Therefore, this specific formula would generally not be considered Reef Safe.
3. Water/Sweat Resistance: The inclusion of Allianz OPT (Acrylates/C12-22 Alkyl Methacrylate Copolymer) is appropriate for water and sweat resistance. However, the proposed 10% usage rate is higher than the typical recommended range (1-5%) for this ingredient and could potentially impact the final texture, making it feel sticky or heavy.
4. Formula Structure (Emulsion Type): The formula lists both oil-soluble/dispersible ingredients (most UV filters, PPG-3 Myristyl Ether, LipidSoft SPF, LipidSoft C1215) and water-soluble/dispersible ingredients (Disodium EDTA, Extreme-B3, Panthenol, Portulaca Extract, Licorice Extract, Bisoctrizole, Allianz OPT, Mild Preserved Eco, Water). However, a primary emulsifier is missing from your ingredient list. An emulsifier is essential to create a stable blend of oil and water phases. Without it, the formula will likely separate.
5. Water Content: The water content is only 3%. This is extremely low for most emulsion types (like O/W or W/O) and will make it very challenging to dissolve/disperse the water-soluble/dispersible ingredients and create a stable, aesthetically pleasing texture. The formula appears heavily weighted towards the oil/powder phase (totaling around 97%).
6. Ingredient Levels: Some levels, like PPG-3 Myristyl Ether (10%), LipidSoft SPF (10%), LipidSoft C1215 (20%), and Allianz OPT (10%), are quite high. While these contribute to dissolving filters and film-forming, their combined high percentage, coupled with low water, will significantly influence the final texture and stability.
7. Extracts and Actives: The inclusion of Extreme-B3, Portulaca Extract, Centella Asiatica Extract (Pure-TECA™), and Licorice Extract provides beneficial skincare properties. Their percentages seem reasonable.
8. Texture Enhancers: SelectSorb and PMMA Booster are good additions for oil absorption, texture improvement, and SPF boosting.

Recommended Adjustments

• Add a Primary Emulsifier: You must include a suitable primary emulsifier system (or a blend) compatible with your chosen oil and water phases and UV filters. The type and amount will depend on the desired texture (lotion, cream, etc.) and emulsion type (O/W, W/O).
• Adjust Water/Oil Ratio: Significantly increase the water content and decrease some of the oil/emollient phases (PPG-3 Myristyl Ether, LipidSoft SPF, LipidSoft C1215) to achieve a more balanced and stable emulsion, and better dissolve/disperse water-based ingredients. The exact ratio will depend on the chosen emulsifier and desired texture.
• Review Allianz OPT Level: Consider reducing the Allianz OPT to within the recommended range (1-5%) unless extensive testing proves stability and acceptable aesthetics at 10%. You might need to explore other film formers or water-resistant additives if a higher level is necessary for performance but causes texture issues.
• Consider Reef Safe Alternatives: If Reef Safe is a strict requirement, you would need to reformulate using mineral filters (Zinc Oxide, Titanium Dioxide), possibly in combination with some of the organic filters that are less controversial, although achieving high SPF/PA and good aesthetics with mineral-only formulas can be challenging.

Recommended Mixing Method (General Guideline - Requires Emulsifier)

This is a general guideline and will need adjustment based on the specific emulsifier system chosen and the final water/oil ratio. Always follow the supplier's instructions for each raw material.

1. Water Phase (Phase A): Combine Water, Disodium EDTA, Extreme-B3, Panthenol, Portulaca Extract, Licorice Extract, and Allianz OPT. Heat gently if needed, but avoid prolonged high heat for extracts. Ensure all water-soluble ingredients are dissolved and Allianz OPT is dispersed.
2. Oil Phase (Phase B): Combine PPG-3 Myristyl Ether, LipidSoft SPF, LipidSoft C1215, Drometrizole Trisiloxane, Ethylhexyl Triazone, BEMT, DHHB, and your chosen primary emulsifier(s). Heat Phase B to around 80°C (or as recommended by suppliers) to fully dissolve the powder UV filters. Ensure all components are homogenous.
3. Combine Phases: Slowly add Phase B to Phase A (or Phase A to Phase B, depending on the emulsifier type and desired emulsion) while mixing with high shear to create the emulsion.
4. Cooling Phase: Continue mixing while cooling the emulsion. Add Bisoctrizole (water-dispersible) during the cooling phase, ensuring it is well dispersed.
5. Final Additions: Once the emulsion has cooled sufficiently (e.g., below 40°C), add heat-sensitive ingredients like Mild Preserved Eco. Disperse powders like Pure-TECA™ (pre-dispersed in glycol if needed), SelectSorb, and PMMA Booster into the cooled emulsion and mix until homogenous.
6. Adjust pH: Check and adjust the final pH if necessary, ensuring it is suitable for the ingredients and desired product stability.

Conclusion

The proposed formula has the potential for high UV protection but requires significant adjustments, particularly the addition of a primary emulsifier and balancing the water and oil phases for stability and texture. It is also important to note that this formula, using only organic filters, is not typically considered Reef Safe. Developing a stable and effective sunscreen requires careful formulation, pilot batches, stability testing (including freeze-thaw and elevated temperature), and mandatory in-vivo or in-vitro SPF/PA testing to confirm the final protection values and water resistance claims.

It is highly recommended to work with an experienced formulator for complex sunscreen formulations like this one.