Increasing PA from PA++ to PA+++

To increase the PA (UVA protection) of your sunscreen formula from PA++ to PA+++, you will need to incorporate additional UVA filters or increase the concentration of your current broad-spectrum filter if it provides sufficient UVA protection at higher levels.

Your current formula uses 15% SPF Protect Ultra™ II, which provides SPF 50.95 and PA++. To reach PA+++, consider the following options:

• Add a dedicated UVA filter: You can add ingredients known for strong UVA protection to your existing formula. Suitable options include:

  • BEMT (Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine): Highly effective and stable UVA/UVB filter. Recommended usage is typically 1-10%.
  • Bisoctrizole (MBBT): Provides broad-spectrum protection including UVA I and UVA II. Easy to disperse in water. Usage rate is 1-10%.
  • Drometrizole Trisiloxane (Mexoryl XL): A stable and effective UVA filter. Usage rate is 1-15%.

• Increase the concentration of SPF Protect Ultra™ II: While 15% gives PA++, increasing the concentration might increase the PA. However, the product description for SPF Protect Ultra™ II at 30% still indicates PA++. It might be more effective to use a different or additional filter specifically for UVA.

• Consider using SPF Protect Ultra™ III: This blend is designed to provide higher SPF and PA values. At 20%, it provides SPF ~50, PA++. At 25%, it provides SPF ~70-100. Increasing the concentration of SPF Protect Ultra™ III in your formula could potentially help achieve PA+++.

Achieving a specific PA rating often requires laboratory testing to confirm the protection level. You may need to experiment with the concentration of the added UVA filter or the alternative SPF Protect Ultra™ III to reach PA+++ while maintaining desired texture and stability.

It is recommended to start with a lower percentage of the additional UVA filter (e.g., 1-3%) and adjust as needed based on testing.

Remember to check the maximum allowed usage rates for each ingredient according to relevant regulations (e.g., FDA).