BB Cream Formulation Adjustment for High SPF, Water Resistance, and Stability

English Answer:

Regarding your request to adjust your BB cream formula for SPF 35/higher, water resistance, longevity, better coverage, and to prevent color dropping:

1. Increasing SPF:

   • Your proposed SPF 50+ formula using BEMT 3%, Zinc Oxide 10%, Titanium Dioxide 4%, and Tris-Biphenyl Triazine (Nano) 5% can indeed achieve SPF 50 according to the staff's calculation.
   • However, the staff noted that BEMT at 3% might not fully dissolve in the oil phase with only 10% LipidSoft. You may need to reduce the BEMT percentage or add more oil-soluble solvent (like OMC) to ensure complete dissolution during the heating step.

2. Coverage and Color Dropping:

   • Adding BB Micro Silk is a good approach to improve coverage and skin feel (smoothness).
   • The sunscreens in your proposed SPF 50+ formula (BEMT, Zinc Oxide, Titanium Dioxide, Tris-Biphenyl Triazine) are stable and are not known to cause color dropping due to degradation, unlike some other sunscreens (Avobenzone, OMC).
   • The staff confirmed that Zinc Oxide 200nm EasyDisperse™ has very little whitening effect compared to Titanium Dioxide.

3. Silicone Gel Base and Cyclomethicone:

   • You can include Silicone Gel Base (Ultra Clear) and Cyclomethicone in the oil phase if desired. However, remember they contribute to the total oil percentage.

4. High Oil Phase and Water-Capsule™ Stability:

   • Your proposed formula has a high oil phase percentage (37%). While the staff has seen Water-Capsule™ work with higher oil percentages (up to 45% with Pro Polymer), 37% is above the typical recommendation (<= 25%) and may affect the long-term stability of the emulsion.

5. Water Resistance:

   • Using Water-Capsule™ creates a Water-in-Oil (W/O) emulsion, which provides good water resistance suitable for handling heavy sweating, much better than an Oil-in-Water (O/W) formula.

6. Mixing Steps:

   • The mixing steps provided by the staff are suitable for your proposed formula:
     • Mix the oil phase ingredients and heat to 70°C to dissolve oil-soluble chemical sunscreens like BEMT.
     • Mix the water phase ingredients until a gel forms.
     • Add the oil phase to the water phase and mix gently until uniform.

7. SPF Protect Ultra™ Stinging:

   • As the staff mentioned, the best way to identify which ingredient in SPF Protect Ultra™ caused the stinging is to test the individual components.

8. Tris-Biphenyl Triazine (Nano) Stock:

   • The stock date mentioned in the conversation (April 1, 2016) is outdated. I cannot provide current stock availability information.

In summary, your SPF 50+ formula is feasible in terms of sun protection, provides good water resistance with Water-Capsule™, and the sunscreens used are stable against dropping. Pay attention to dissolving BEMT and note that the high oil phase might impact long-term stability. Adding BB Micro Silk will enhance coverage.