Sunscreen Formulation: Texture, Primer, and Base Options

Question

I am formulating a sunscreen using SPF Protect Ultra. I would like the texture to be light and smooth, and ideally, it should also function as a primer. Is Disodium EDTA necessary when using distilled water (TDS 0.02)? What adjustments are needed to achieve a light, smooth texture with SPF Protect Ultra? (Considering options like Pro Polymer or Silky Serum Base Plus) Can the resulting formula be used as a primer?

MySkinRecipes Expert · Accepted Answer

Sunscreen Formulation Questions

Based on the feedback and product information, here are the answers to your questions:

Can the original formula using Silky Serum Base be used?
The staff's initial assessment is correct. The original formula with 20% Silky Serum Base and 20% SPF Protect Ultra is not feasible because Silky Serum Base is not designed to hold a large amount of oil, and SPF Protect Ultra contains oily components. While Silky Serum Base contains silicones and SiliSolve, the base itself at that concentration cannot properly emulsify or stabilize the high oil load from the sunscreen active, leading to separation.
Is Disodium EDTA necessary with distilled water?
Even when using distilled water with low TDS, adding Disodium EDTA is optional but can be beneficial. It helps to chelate any trace metal ions that might still be present and can contribute to the overall stability and shelf life of the formula.
What adjustments are needed for a light, smooth texture?
To achieve a light and smooth texture that can incorporate SPF Protect Ultra, the suggested alternative formulas are more suitable:
- Using Pro Polymer Silk: The staff suggested a formula using Pro Polymer Silk (1%), SPF Protect Ultra (20%), Silicone Gel (5%), Cyclomethicone (5%), and the rest water/preservative. Pro Polymer Silk acts as a gel maker that can also hold a limited amount of oil/silicone, providing a smooth feel.
- Using Silky Serum Base Plus: Cosmeceutical7 suggested a formula using Silky Serum Base Plus (10%), SPF Protect Ultra (15%), and Water (75%). Silky Serum Base Plus is specifically designed to coordinate both water and oil/silicone phases, creating a water-in-silicone/oil emulsion. This type of emulsion typically offers a very light, smooth feel and enhanced water resistance.
Can the formula be used as a primer?
Yes, the formula using Silky Serum Base Plus is suitable for use as a primer. As Cosmeceutical7 explained, this base creates a water-in-silicone/oil structure that leaves a silicone film on the skin. This film provides a smooth surface that helps makeup adhere better and last longer, effectively functioning as a primer.