Sunscreen Formulation Questions

Here are the answers to your questions regarding the liquid spray sunscreen formulation:

1. Suitability for Liquid Spray (Non-Aerosol) with SPF 50 and PA+++:
   The formula you provided, using Titanium Dioxide 15nm Liquid and Zinc Oxide 35nm Liquid, is designed as a water-in-oil emulsion. Both ingredients are in liquid dispersion form, which helps in creating a smoother, more fluid texture compared to using powders. The example formula provided in the description of Zinc Oxide 35nm Liquid is exactly the one you listed, and the description for Titanium Dioxide 15nm Liquid shows a similar formula achieving SPF 51.06, PA++. While the formula is a liquid emulsion, its suitability for a specific non-aerosol spray head depends on the final viscosity achieved. The provided formula is a good starting point for a liquid sunscreen, and with potential minor adjustments to viscosity (e.g., using viscosity modifiers mentioned in the ingredient descriptions like waxes or Hectorite Gel if needed, though for a spray, lower viscosity is desired), it can likely be formulated into a liquid suitable for a pump spray, achieving SPF 50 and PA+++ based on the ingredient concentrations and typical performance.

2. Using PMMA Booster at 3% and Reducing Sunscreen Agents:
   Using PMMA Booster (SPF/Color Booster) at 3% is appropriate for boosting SPF/PA. According to the product description, a 2-3% usage rate can increase the SPF value by at least 30% and PA at the same rate. This means adding 3% PMMA Booster to your formula should significantly enhance the SPF and PA values. Because PMMA Booster works by improving the light distribution and efficiency of the UV filters (Titanium Dioxide and Zinc Oxide), it can potentially allow you to reduce the concentration of Titanium Dioxide 15nm Liquid and Zinc Oxide 35nm Liquid while still achieving your target SPF 50 and PA+++. However, the exact amount by which you can reduce them would need to be determined through testing, as it depends on the specific interaction within your full formula.

3. Free SPF Testing Service:
   The free SPF measurement service is available when you use PMMA Booster (SPF/Color Booster) in your formulation to help boost SPF/PA values. To proceed with this service, you should contact the company directly to inquire about the process, requirements, and scheduling for submitting your sample for testing. The product descriptions mention this service is offered, but the specific steps for arranging it would be handled through direct communication with the company.